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Exam 2: Notes in RED

Terms

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Any drug that is centrally acting should be tapered off____________when no longer needed.
Over 2 to 3 Weeks
Inhalational Anesthetics
Volatile liquids or gases that are vaporized in oxygen and inhaled
Parenteral Anesthetics
Used: to induce or maintain general anesthesia, to induce amnesia, as an adjunct to inhalation type anesthetics
Ketamine (Ketalar)
Used for General and Moderate Sedation -Given Intravenously -Low incidence of reduction of cardiovascular, respiratory, and bowel function -Come back really fast from it
Propofol (Diprivan)
Used for the induction and maintenance of general anesthesia -Also for sedation for mechanical ventilation in ICU -Also be used as a sedative-hypnotic for moderate sedation in lower doses -Few undesirable effects -Come back really fast from it
Benzodiazepines
Produce unconsciousness, or amnesia -Occasional respiratory suppression
Malignant Hyperthermia
High temp. / Tachycardic / Muscles get ridged
Lidocaine (Xylocaine)
Most widely used local anesthetic -Topical and injectable applications -Effects extended if given with epinephrine -Also used for cardiac dysrhythmias Preparations: Cream, Ointment, Jelly, Solution, Aerosol, Patch
Locals
Apply topicals to smallest surface area; avoid abraded / injured skin
Patient may be paralyzed yet conscious
Neuromuscular Blocking Drugs
Succinylcholine (Anectine)
Result: Flaccid muscle paralysis Duration: 5-9 minutes
Morphine sulfate, fentanyl, codeine sulfate, meperidine HCI (Demerol)
Opioid Agents
Status prior to drug and 1 hour after PO; 15 minutes for IVP
Clinical Use of Opioids
Withdraw slowly and taper for those on high doses of opioids for Greater than or equal to 20 Days
Opioid Dosing Guidelines: Avoiding Withdrawal
Physical Dependence
A state in which and abstinence syndrome will occur if the dependence-producing drug is abruptly withdrawn-NOT equated with addiction
Abuse
Drug use that is inconsistent with medical or social norms: reason & setting dependent
Addiction
A behavior pattern characterized by continued use of a psychoactive substance despite physical, psychologic, or social harm
Patient-controlled analgesia
As needed pain relief for post op patients; also those with cancer, trauma, MI, sickle cell crisis and labor
Postoperative pain
*Clinical Use of Opioids* Obstetric analgesia; meperidine preferred
Myocardial infarction: morphine is DOC
*Clinical Use of Opioids* Lowers BP & reduces cardiac work
Cancer-related pain
*Clinical Use of Opioids* object is to maximize comfort; minimal concern about psychologic or physical dependence
Chronic non-cancer pain
*Clinical Use of Opioids* opioids should no be withheld; Guidelines for use
Toxicity and Management of Opioid Overdose
Naloxone (Narcan) Naltrexone (Revia) -These drugs bind to opiate receptors and prevent a response -Used for complete or partial reversal of opioid-induced respiratory depression
Morphine
Strong opioid agonist - Prototype Source: Seedpod of the poppy plant Schedule II controlled substance; High abuse potential -Relief of moderate to severe pain
Fentanyl (Sublimaze, Duragesic)
*Strong Opioid Agonist -100 times the potency of morphine -Levels can be increased by CYP3A4 inhibitors (ritonavir, ketoconazole)
Fentanyl (Sublimaze, Duragesic)
**Five formulations in three routes-Parenteral (Sublimaze) *Surgical anesthesia -Transdermal (Duragesic and lonsys) *Patch -72hrs -heat acceleration; for persistent pain; opioid tolerant -Transmucosal *Lozenge on a stick (Actiq) *Buccal lozenges (Fentora)
Meperidine (Demerol)
*short half-life requires repeat dosing *Interacts adversely with several other drugs *Toxic metabolite accumulation with continuous use, therefore, routine use is avoided *Given for patients who cannot take opioids, and for pts with drug induced rigors on postanesthesia
Methadone hydrochloride (Dolophine)
-tx for cancer and neuropathic pain -for the detox and tx of opioid addiction -Rapid absorption from GI tract -Very long half life: allows for 24hr dosing -Can be toxic
****Similar to morphine in most**** respects: -Produce analgesia, sedation, euphoria -Can cause; respiratory depression, constipation, urinary retention, cough suppression, and miosis *Can be reversed with naloxone **Different from morphine** -Produce less analgesia and respiratory depression than morphine -Somewhat lower potential for abuse
Codeine, Oxycodone, Hydrocodone
Hint: in applying information on this Pharm Exam
Why you use these drugs? Who is going to be treated? Why they will be treated? What route should be used? Example; by transdermal patch, orally, or injection
Codeine
-For mild to moderate pain -Actions and uses 10% of each dose converts to morphine in liver -Pain and cough suppression -Possesses a Ceiling Effect -Preparations, dosage, and administration -Usually PO (formulated alone or with aspirin or acetaminophen); combos provide ↑ pain relief -Side effects are dose limiting: 30 mg produces same effect as 325 mg acetaminophen -Effects of CYP2D6 gene -Schedule II alone; Combos in Schedule III; -Cough combo agents in Schedule V
Oxycodone (OxyContin, Oxy IR, Roxicodone, Percodan, Percocet, etc)
-Structurally related to morphine -Analgesic actions equivalent to those of codeine -Available by itself or in combo with ASA, acetaminophen, ibuprophen) -A long-acting analgesic -Immediate release (Oxy IR) -Controlled release (OxyContin) -Moderate to severe pain -Abuse: crushes and snorts or injects medication -Nursing considerations:
Hydrocodone (Vicodin, Lortab)
-Most widely prescribed drug in the United States -Combined with aspirin, acetaminophen, or ibuprofen -Analgesic actions equiv to codeine -Used for pain and relief of cough
Pentazocine (Talwin) - Prototype
-Actions and uses - for mild to mod pain; less effective than morphine against severe pain -Agonist at kappa receptors & antagonist at mu receptors -Limited resp depression; no euphoria; low abuse potential -Adverse effects: like morphine except increases cardiac work load -WILL PRECIPITATE WITHDRAWAL IN OPIOID DEPENDENT PTS - BLOCKS MU RECEPTORS - NEVER GIVE TO A PT PHYSICALLY DEPENDENT ON A PURE OPIOID AGONIST!
Nalbuphine (Nubain)
-Agonist at kappa receptors; antagonist at mu receptors -Analgesia like morphine, but has a ceiling to amount of analgesia -Physical dependence possible with prolonged use -Not to be used in labor & delivery -Can cause withdrawal in opioid dependant pts
Butorphanol (Stadol)
like pentazocine
Buprenorphine (Buprenex)
-Partial agonist at mu receptors; antagonist at kappa receptors -Cannot readily be reversed by naloxone
Opioid Antagonists
*Naloxone (Narcan) *Methylnaltrexone (Relistor) *Naltrexone (ReVia, Depade)
Principal Uses of Opioid Antagonists
-Treat opioid overdose, relief of opioid-induced constipation -Reversal of post-op opioid effects (resp depression, ileus) -Management of opioid addiction
Naloxone (Narcan)
-Competitive antagonists at opioid receptors -Therapeutic uses -Reversal of opioid overdose -Drug of choice with pure opioid agonist overdose -Titrate cautiously with physical dependence -Reversal of postoperative opioid effects -Titrate to achieve adequate ventilation and maintain pain relief -Reversal of neonatal respiratory depression -Opioids given during labor and delivery may cause respiratory depression in neonate
Methylnaltrexone (Relistor)
LATE STAGE CANCER PATIENTS*** GIVEN SUBQ -Selective mu opioid antagonist -Tx of opioid-induced constipation in late-stage disease for patients on constant opioids who have not responded to traditional (standard) laxative therapy -Given subQ -Works within 30 min to 4 hours -Discontinue if diarrhea develops; Do not use in pts with suspected or known mechanical GI obstruction
Naltrexone (Revia)
Can reverse neonatal respiratory depression
Tramadol (Ultram, Ultram ER)
-Combination of opioid and nonopioid mechanisms -For moderate to moderately severe pain -Given PO; reaches plasma peak levels in 2 hrs -S/E: sedation, dizziness, headache, dry mouth, constipation -Avoid use in pts with epilepsy & neuro disorders d/t seizure risk -Review drug interactions: CNS depressants, MAOIs, Serotonin Syndrome
Clonidine
-Mechanism of pain relief -Alpha2 adrenergic agonist -Analgesic use -Used in combination with opioid analgesic -For tx of hypertension & relief of atypical severe pain -Duraclon for pain relief/epidural infusion; Catapres for hypertension/PO or transdermal patch -Adverse effects -Cardiovascular - severe hypotension d/t massive vasodilation; rebound hypertension, bradycardia -Contraindications -Hemodynamically unstable pts; obstetric, post-partum and surgical pts
Acetaminophen
-Analgesic and antipyretic effects -Little to no antiinflammatory effects -Available over the counter and in combination ****MOA: Similar to salicylates**** Blocks pain impulses peripherally by inhibiting prostaglandin synthesis
Overdose, hepatic necrosis: hepatotoxicity Long term ingestion of large doses also causes nephropathy
Tyelenol or Acetaminophen
Antidote for Tylenol overdose
Acetylcysteine
Ziconotide (Prialt)
-An intrathecal analgesic to be MD administered. -MOA not fully defined. -Indicated for severe, chronic pain refractory to other treatment. -Advantage: not an opioid, may be discontinued abruptly. -Adverse effects: psychosis, neuro impairment, reduced cognitive function, mood & LOC changes & hallucinations.
Use of meperidine should not exceed __________ - avoid toxic metabolite accumulation
48 Hours
Assessment of pain is now being considered a
Fifth Vital Sign
Be sure to medicate patients before the pain becomes severe so as to provide adequate analgesia and _________.
pain control
less than 10 breaths/min, dyspnea, diminished breath sounds, or shallow breathing
Respiratory depression
Name some commonly given Schedule III drugs
-Percocet -Lortab
What is meant by the term "pure opioid agonist?
-Drugs that activate mu and kappa receptors -Found in the CNS -Activation may cause: analgesia, euphoria, sedation, resp depression -Mimic endogenous opioid peptides (enkephalins, endorphins and dynorphins)
What is meant by the term agonist-antagonist or mixed agonist?
-When given alone produce analgesia in the opioid naïve person -In the opioid-tolerant person, produces withdrawal effect -Talwin (pentazocine)
What are the major side effects of morphine pure mu agonist?
-Constipation (slows peristalsis; mush without push) -Sedation (occurs before respiratory depression -Resp depression
What are the major side effects of morphine pure agonist?
Orthostatic hypotension Urinary retention (↑ bladder tone) Cough suppression N and V (stimulates CTZ) Itching Euphoria Miosis ↑ ICP (↓ resp → ↑ CO2 retention) Myoclonus
To which of the previous side effects of mu agonists does a person usually NOT become tolerant?
-Constipation -Rx with not only a stool softener, but a stimulant laxative -Miosis
How can opioids be administered routes?
IM/subQ/IV PO PR Intrathecal SL Epidural Nebulized Topical (patches)
Is there a maximum amount (mg) of opioid that can be administered within a 24 hour period?
No There is no ceiling Must taper up
In what patients should mu agonists (pure opioids) be used cautiously?
Infants Elderly Debilitated pts Opioid naïve pts Pts with biliary problems
If a pt is receiving intraspinal morphine, which exogenous drugs should be withheld?
MAOIs, CNS depressants (including other mu agonists), anticholinergics, alcohol, sedative-hypnotics, antihistamines, benzos, etc.
What mu agonist should not be given on a chronic basis and why not?
Demerol (meperidine) Toxic metabolite (normeperidine) Can cause seizures Accumulates faster in pts with renal insufficiency 600 mg/day 300 mg/dose (PO)
After surgery, a patient has morphine prescribed for postoperative pain. Which is the priority assessment in this situation? A. Respiratory rate B. Heart rate C. Pain level D. Constipation
Respiratory rate
A patient with cancer complains of bone pain rated 8 (on a 0 to 10 pain scale). Which as needed (PRN) medication should the nurse administer? A. Ibuprofen (Motrin) B. Acetaminophen (Tylenol) C. Hydromorphone (Dilaudid) D. Meperidine (Demerol)
Hydromorphone (Dilaudid)
Which is the priority of care in the patient with moderate to severe pain from cancer? A. Prevention of addiction and physical dependence B. Adequate pain relief with opioid medications C. Avoiding constipation by increasing dietary fiber D. Using transcutaneous electrical nerve stimulation (TENS) or massage to treat cancer pain
Adequate pain relief with opioid medications
For best results when treating severe pain associated with pathologic spinal fractures related to metastatic bone cancer, the nurse should remember that the best type of dosage schedule is to administer the pain medication A. as needed. B. around the clock. C. on schedule during waking hours only. D. around the clock, with additional doses as needed for breakthrough pain
around the clock, with additional doses as needed for breakthrough pain
A patient is receiving an opioid via a PCA pump as part of his postoperative pain management program. During rounds, the nurse finds him unresponsive, with respirations of 8 breaths/min and blood pressure of 102/58 mm Hg. After stopping the opioid infusion, what should the nurse do next? A. Notify the charge nurse B. Administer oxygen C. Administer an opiate antagonist per standing orders D. Perform a thorough assessment, including mental status examination
Administer an opiate antagonist per standing orders
A patient with bone pain caused by metastatic cancer will be receiving transdermal fentanyl patches. The patient asks the nurse what benefits these patches have. The nurse's best response includes which of the following features? A. More analgesia for longer time periods B. Less constipation and minimal dry mouth C. Less drowsiness than with oral opioids D. Lower dependency potential and no major adverse effects
More analgesia for longer time periods
The nurse suspects that a patient is showing signs of respiratory depression. Which drug could be the cause of this complication? A. naloxone (Narcan) B. hydromorphone (Dilaudid) C. acetaminophen (Tylenol) D. ziconotide (Prialt)
hydromorphone (Dilaudid)
A patient is recovering from an appendectomy. She also has asthma and allergies to shellfish and iodine. To manage her postoperative pain, the physician has prescribed patient-controlled analgesia (PCA) with hydromorphone (Dilaudid). Which vital sign is of greatest concern? 1. Pulse 2. Blood pressure 3. Temperature 4. Respirations
Respirations
Transdermal fentanyl patches are the preferred forms of opioids for opioid-naive patients. 1. True 2. False
False
A patient who has metastasized bone cancer has been on transdermal fentanyl patches for pain management for 3 months. He has been hospitalized for tests and has told the nurse that his pain is becoming "unbearable." The nurse is reluctant to give him the ordered oxycodone for pain because the nurse does not want the patient to get addicted to the pain medication. The nurse's actions reflect: 1. Appropriate concern for the patient's best welfare. 2. Appropriate caution for a patient who is already on a long-term opioid. 3. An uncaring attitude toward the patient. 4. A failure to manage the patient's pain properly
A failure to manage the patient's pain properly
Accidental or intentional overdose of acetaminophen is rarely a problem because the drug is an over-the-counter product. 1. True 2. False
False
A patient with a history of heavy alcohol use needs a medication for pain. The recommended maximum daily dose of acetaminophen for this patient would be: 1. 1000 mg. 2. 2000 mg. 3. 3000 mg. 4. 4000 mg
2000 mg
A physician orders a 25 mcg patch of fentanyl (Duragesic) to be applied immediately post-op on a 10 year old opioid naïve patient. What action do you take?
Consult with MD Patch not for acute pain For pts who are opioid tolerant 6 --12 - 24 hours to work Not good for acute pain Nor for under 12 Not for < 110 lbs Heat ↑ absorption
How often should Fentanyl patches be changed? How should they be disposed of?
Changed every 72 hours (maybe every 48 hours) Rotate sites Flushed down toilet (with another nurse) May need multiple patches (date them)
How does the transmucosal fentanyl system work (Actiq)?
Designed for acute pain (Breakthrough) Rub unit over buccal mucosa Drug absorbed through MM and stomach Consume all of it (run under hot water) Onset: 5-10 minutes; duration: about 6 hours
Why are oral opioids often combined with aspirin, acetaminophen or ibuprofen?
Potentiates action of opioids Reduces opioid dose Are the dose limiting drug of a combination agent
What is the best method of administration of opioids for a patient with pain anticipated to last over 12 hrs per 24 hours?
Around the clock PCA
Drug Tolerance
Increasing amounts of opioid needed to achieve a similar analgesic effect A common physiological result of chronic opioid tx
Physical Dependence
Confirmed by abstinence syndrome when drug abruptly stopped Develops in all pts on opioids around the clock for about a week
What do pure opioid antagonists do?
Block the mu and kappa receptors. Used to reverse respiratory (RR <8) and CNS depression caused by opioids Note: not used to reverse analgesia!!
When giving Naloxone IVP to reverse the respiratory depressive effects of an opioid, what must the nurse evaluate?
Respirations!!! Depth and rate (while sleeping: > 8) Naloxone short half-life; thus metabolized quickly, before reversing all opioid So, resp depression could return
Describe how to administer Naloxone IV
Take one amp of Naloxone (0.4 mg) Add 9 mL saline Give at 1-2 mL/min Watch RR Stop once RR reaches 8 Do not want to reverse analgesia, only want to ↑ RR
A postoperative patient who has an intravenous infusion of morphine has a respiratory rate of 8 breaths per minute and is lethargic. Which as needed (PRN) medication should the nurse administer to the patient? A. Methadone (Dolophine) B. Nalbuphine (Nubain) C. Tramadol (Ultram) D. Naloxone (Narcan)
...
No cure for motor symptoms Drug therapy can maintain functional mobility for years. Prolongs and improves quality of life
Parkinson's Disease (PD)
Contributes to the motor symptoms of PD
Overactivity of GABA neurons
Dyskinesias
Tremor at rest Rigidity Postural instability Bradykinesia (slowed movement) Tremor Akinesia (late stages) In addition to motor symptoms Autonomic disturbances Depression Psychosis and dementia
Classic Parkinsonian Symptoms
Akinesia, Bradykinesia Rigidity Tremor, Postural instability
Reduction in or absence of psychomotor activity resulting in masklike facial expression and impaired postural reflexes
Akinesia
Slowness of movement "Cogwheel" rigidity, resistance to passive movement.
Bradykinesia Rigidity Tremor
Unsteadiness that leads to danger of falling; hesitation in gait as patient starts or stops walking
Postural instability
Drug Therapy for Parkinson's Disease
The problem: too little striatal dopamine and too much Ach The solution: give drugs that can restore the functional balance between dopamine and ACh Two major categories Dopaminergic agents By far the most commonly used drugs for PD Promote activation of dopamine receptors Levodopa (Dopar) (Prototype) Anticholinergic agents Prevent activation of cholinergic receptors (blockade of muscarinic receptors in the striatum) Benztropine (Cogentin) (Prototype) & others
Dopaminergic agents
Dopamine Replacements Levodopa, Levodopa-carbidopa, Carbidopa Dopamine Agonists/(Non-dopamine receptor agonists) Pramipexole, Ropinirole, Apomorphine (Non-ergot Derivatives) Bromocriptine (Ergot Derivative) COMT Inhibitors Entacapone, Tolcapone Dopamine Releaser - Amantadine MAO-B Inhibitors - Selegiline, Rasagiline
Dopamine Replacements
Levodopa (drug "holidays" recommended) Levodopa/carbidopa
Dopamine agonists
Pramipexole (Mirapex) Entacapone (Comtan) Amantadine (Symmetrel) Selegiline (Eldepryl, Carbex)
CNS Drugs-Parkinsons slide 8
FLASHCARD SET STARTING AT 194
****Know DILANTON and how we treat seizure******
****************
Partial (focal) seizures
Simple partial Complex partial Secondarily generalized
Generalized seizures
Tonic-clonic (grand mal) Absence (petit mal) Atonic Myoclonic Status epilepticus (SE) Febrile
Antiepileptic Drugs Effects
Suppress discharge of neurons within a seizure focus Suppress propagation of seizure activity from the focus to other areas of the brain
Antiepileptic Drugs Mechanisms of Action
Suppression of sodium influx Suppression of calcium influx Antagonism of glutamate Potentiation of GABA
Epilepsy: Therapeutic Considerations
Monitoring plasma drug levels Promoting patient adherence-priority *Educate patients and families *Monitor drug levels *Seizure frequency chart Withdrawing antiepileptic drugs - rule *AEDs must be withdrawn slowly; if 2 drugs, withdraw sequentially Suicide risk - antiepileptic drugs *Monitor pts for anxiety, agitation, mania, hostility *Teach pts, family/caregiver to be alert for sxs Therapy is long term, possibly life long; not a cure
Classification of Antiepileptic Drugs (AEDs)
Two major categories: 1st line Drugs *Traditional antiepileptic drugs (AEDs *Phenytoin, carbamazepine, valproic acid, & phenobarbital Newer AEDs *levetiracetam (Keppra), topiramate (Topamax), zonisamide (Zonegran), tiagabine (Gabitril), and pregabalin (Lyrica)
Antileptic drugs should be withdrawn quickly or slowly?
Slowly
Phenobarbital (Luminal)
One of oldest drugs - effective, inexpensive, once a day dosing Belongs to barbiturate family - anticonvulsant barbiturate Uses: Epilepsy (partial and generalized tonic-clonic seizures) Promotes sleep and sedation SE: lethargy, depression, learning impairment Use in pregnancy - risk to fetus; bleeding risks Drug withdrawal - reduce dose gradually to avoid SE. Warn pts not to discontinue too quickly
phenobarbital (Luminal)
Since 1912; still widely used d/t low cost. Sedative, but tolerance to this develops. Therapeutic effects at serum drug levels of 15 to 40 mcg/mL. Advantage: long half-life, allows once daily dosing. Adverse effects: cardiovascular, CNS, gastrointestinal (GI), and dermatologic reactions . Many drug interactions: major inducer of P-450 system.
Phenytoin (Dilantin)
Most widely used; side effects Partial and tonic-clonic seizures Mechanism of action: selective inhibition of sodium channels; action potentials suppressed, thus drug suppresses activity of seizure-generating neurons Varied oral absorption Half-life: 8 to 60 hours Therapeutic level: 10-20 mcg/mL
Dose & Plasma Drug Level for Phenytoin vs. Other Drugs
Within the therapeutic range, small increments in phenytoin dosage produce sharp increases in plasma drug levels. This relationship makes it difficult to maintain plasma phenytoin levels within the therapeutic range
Phenytoin, or Dilantin
Cannot mix with anything but Normal Saline
Phenytoin (Dilantin) - Adverse effects
Nystagmus, ataxia, dysarthria & encephalopathy at toxic levels. Sedation, lethargy, abnormal movements, mental confusion, diplopia & cognitive impairment are common adverse effects. Gingival hyperplasia - well known adverse effect & Skin rash(measles-like), acne, hirsutism and hypertrophy of subcut facial tissue - adverse effects with long term therapy Effects in pregnancy- teratogenic; bleeding tendencies in newborns; Vit K to mom & baby Cardiovascular effects - IV - inject slowly
Phenytoin, or Dilantin - Drug interactions
Highly protein bound & inducer of P-450 system. Decreases the effects of oral contraceptives, warfarin, and glucocorticoids Increases levels of diazepam, isoniazid, cimetidine, alcohol, and valproic acid
Fosphenytoin (Cerebyx)
An injectable prodrug of phenytoin. Should not exceed 50 mL / min Can be given IM or IVP or by continuous infusion. Dosed in phenytoin equivalents (PE), 150 mg / min
Carbamazepine (Tegretol) - Uses
Epilepsy Bipolar disorder Trigeminal and glossopharyngeal neuralgias
Carbamazepine (Tegretol) - Adverse effects
Neurologic effects: nystagmus, ataxia Hematologic effects: leukopenia, aplastic anemia, thrombocytopenia; agranulocytosis. Birth defects Hypo-osmolarity Dermatologic effects: rash, photosensitivity reactions
***Valproic Acid (Depakene, Depakote, Depacon) - Uses
Seizure disorders (generalized and partial) Bipolar disorder Migraine
***Valproic Acid (Depakene, Depakote, Depacon) - Adverse effects
GI effects (n/v); drowsiness; tremor, weight gain Hepatotoxicity: liver failure Pancreatitis - warn patients of s/s Teratogenic effects
Valproic Acid (Depakene, Depakote, Depacon) - Drug interactions
highly protein bound & highly metabolized by P-450 system.
Ethosuximide (Zarontin)
Drug of choice for absence seizures
Newer Antiepileptic Drugs
Gabapentin (Neurontin) Pregabalin (Lyrica) Lamotrigine (Lamictal) Levetiracetam (Keppra) Tiagabine (Gabitril) Topiramate (Topamax) Zonisamide (Zonegran)
Management of Generalized Convulsive Status Epilepticus
Continuous series of tonic-clonic seizures, lasting at least 20 to 30 min with loss of consciousness. Tachycardia, ↑BP, hyperthermia ***Can cause permanent neuro damage if persists >20 min ***Medical emergency ***Goals of treatment Maintain ventilation Correct hypoglycemia Terminate seizures ***IV benzodiazepines (lorazepam or diazepam
Management of Generalized Convulsive Status Epilepticus
Diazepam (Valium) DOC to control seizures Short duration of action (72 hours) Requires repeat administration Once seizures controlled, need drugs for long-term seizure suppression (AED) Initial dose: 10 mg at 2 mg/min Repeat in 5-10 minutes if needed
What effect will concurrent administration of cimetidine (Tagamet) have on phenytoin?
Will decrease the rate at which phenytoin is metabolized, thus will increase phenytoin levels and can lead to potential toxic effects. Valium, INH, ETOH, and valproic acid & many others do the same
Name some drugs known to decrease phenytoin levels
Carbamazepine Phenobarbital
Drugs whose plasma levels can be reduced when phenytoin is given concurrently include...?
1. oral contraceptives 2. warfarin 3. glucocorticoids
Describe how you would administer phenytoin (300 mg) IVP.
Give no faster than 50 mg/min in adults. In the elderly: no faster than 25 mg/min (CV collapse) Follow with saline flush to avoid venous irritation. Mix only with normal saline (precipitates in D5W or Ringers Lactate) IV infusion to be avoided. Avoid extravasation. Assess ECG and vital signs during admin (do not give to pts with bradycardia or heart block)
A pt's phenytoin level is reported at 14 mcg/mL. Is this WNL (within normal limits)? Discuss the importance of monitoring plasma drug levels
Normal limits: (Gotta Memorize!!) TL = 10-20 mcg/mL. Monitoring Therapeutic Level (Why?): *> chances of achieving effectiveness *Evaluates adherence to therapy *Aids in finding cause of loss of sx control *ID cause of toxicity
When providing pt education re: anticonvulsant meds, what are the important points to cover?
***Take exactly as prescribed.*** *CNS SE < over time *Avoid driving or using hazardous equip initially *Do not stop drugs abruptly *Avoid other CNS depressants *Avoid OTC meds *Food Effect < absorption *Wear Med-Alert bracelet
Some anti-epileptics cause bone marrow suppression (eg. Aplastic anemia). What symptoms would you describe to the pt to be aware of and to report?
Pallor Weakness Easy bruising Petechiae Fever Sore throat
What water soluble vitamin absorption is often reduced with phenytoin and may require supplementation?
Folic Acid (Main excessive folic acid symptom: Itching!!!)
Which AEDs should be avoided, if possible, during pregnancy?
Valproic Acid Carbamazepine
A woman who has had no seizures while on valproic acid is now pregnant. What do you tell her about AED?
She should take folic acid throughout her pregnancy while continuing to take valproic acid. Folic acid < risk of neural tube defects Have to consider the effects of a seizure on baby.
A woman who has had no seizures on phenytoin (or phenobarbitol) is now pregnant. What do you tell her about AEDs?
> risk for bleeding Should take 20 mg vitamin K QD during last few weeks of pregnancy Baby will be given 1 mg IM of vit K at birth
What are the advantages of fosphenytoin?
Advantages: IVP Can be given with D5W or Ringers Lactate Very effective Many IV incompatibilities exist
What are the disadvantages of fosphenytoin?
Disadvantages: Phenytoin equivalent 150 mg fosphenytoin = 100 mg Dilantin Thus, an order for 100 mg phenytoin equivalent will cause pharmacy to send 150 mg of fosphenytoin which will equal 100 mg of phenytoin (accident waiting to happen)
A patient is prescribed phenytoin (Dilantin) for epileptic seizures. Which of the following is a priority nursing action?
D. Teach the patient to avoid abrupt cessation of treatmen
A patient is newly prescribed carbamazepine (Tegretol) for seizure control. Which food should the patient be taught to avoid?
B. Grapefruit juice
Before a patient is to receive phenytoin (Dilantin), the nurse practitioner orders lab work. Which lab result is of greatest concern?
2. Low serum albumin levels
The nurse is assessing the current medication list of a newly admitted patient. The drug gabapentin (Neurontin) is listed, but the patient states that he does not have any problems with seizures. The nurse suspects that the patient:
3. May be taking this drug for neuropathic pain
A patient with unstable epilepsy is receiving IV doses of phenytoin (Dilantin). The latest drug level is 12 mcg/mL. Which administration technique will the nurse use?
2. Infuse slowly, not exceeding 50 mg/min
A patient in a long-term care facility has a new order for carbamazepine for seizure management. The nurse monitors for auto induction, which will result in
2. Lower than expected drug levels
Two groups of drugs that cause skeletal muscle relaxation
One group for localized muscle spasm Other group for spasticity
Treatment of spasm / Physical Measures
Physical measures Immobilization of affected muscle Cold compresses Whirlpool baths Physical therapy Cyclobenzaprine (Flexeril)
Treatment of Spasm / Drug Therapy
Analgesic anti-inflammatory (aspirin) Centrally acting muscle relaxants Diazepam (Valium) Baclofen (Lioresal) Cyclobenzaprine (Flexeril)
Centrally Acting Muscle Relaxants
*Diazepam (Valium) MOA through enhancing effects of GABA *Baclofen (Lioresal) A derivative of GABA *Cyclobenzaprine (Flexeril) Structurally related to TCAs
Centrally Acting Muscle Relaxants / Mechanism of action
(MOA) unclear - may result from sedative properties of the drugs
Centrally Acting Muscle Relaxants / Therapeutic use
Relieve local muscle spasm Decrease local muscle pain Increase range of motion No studies to indicate superiority of one drug over another
Centrally Acting Muscle Relaxants / Adverse effects
Generalized CNS depression Hepatic toxicity Tizanidine (Zanaflex) and metaxalone (Skelaxin) can cause damage. Chlorzoxazone (Paraflex) can cause hepatitis and necrosis. Physical dependence Abstinence syndrome
Spasticity
Movement disorders of CNS origin Most common causes: multiple sclerosis and cerebral palsy
Three Drugs for Spasticity
Baclofen (Lioresal) Acts in the CNS Diazepam (Valium) Acts in the CNS Dantrolene (Dantrium) Acts directly on smooth muscle
**Baclofen (Lioresal) / Mechanism**
Acts in the spinal cord Suppresses hyperactive reflexes Exact Mechanism unknown May mimic the action of GABA on spinal neurons
**Baclofen (Lioresal) / Therapeutic uses**
Multiple sclerosis, spinal cord injury, cerebral palsy NOT with stroke Decreases flexor and extensor spasms Suppresses resistance to passive movement ***No direct effect on skeletal muscle***
Diazepam (Valium)
Member of the *benzodiazepine* family (see Chapter 34) **The only one labeled to treat spasticity* *Mechanism: Acts in the CNS Mimics action of GABA *Adverse effect *Sedation*
Dantrolene (Dantrium)
Mechanism *Acts directly on skeletal muscle *Suppresses the release of calcium from the sarcoplasmic reticulum (SR) Therapeutic uses *Spasticity associated with multiple sclerosis, cerebral palsy, spinal cord injury *Malignant hyperthermia Potentially fatal condition caused by succinylcholine and general anesthetics
Dantrolene (Dantrium) / Adverse effects
Hepatic toxicity Muscle weakness Drowsiness Diarrhea Acne-like rash
How is Baclofen thought to work? (anti-spasticity)
Mimics the action of GABA on spinal neurons No direct effect on skeletal muscle
What patient education is necessary for those taking centrally acting muscle relaxants?
CNS depression: drowsiness, dizziness, lightheadedness, fatigue Avoid driving, operating hazardous equipment Avoid other CNS drugs (ETOH, opioids, antihistamines, benzos)
What other nursing interventions are important with Baclofen?
Pt should ambulate with assistance. Monitor vital signs, LOC and sedation levels. Teach pts to change position slowly to prevent syncope or dizziness. DO NOT WITHDRAW ABRUPTLY; taper to prevent hallucinations, paranoia & seizures. This med is taken 3-4 times daily.
How does dantrolene work?
Acts directly on skeletal muscle by suppression of calcium from sarcoplasmic reticulum, which < ability of skeletal muscle to contract. Thus: a peripherally acting MR
With muscle relaxants on tests
Think about patient safety
For what anesthesia complication is dantrolene used to treat?
Malignant hyperthermia
A patient is prescribed metaxalone (Skelaxin). The nurse will teach the patient to immediately report:
B) yellow skin color (indicative of liver failure)
A patient with multiple sclerosis is prescribed baclofen (Lioresal). The nurse will observe the patient for which intended effect
B) Spasticity suppression
**Baclofen (Lioresal) / Adverse Effects**
Adverse effects: No antidote for overdose Gradual withdrawal over 1 to 2 weeks With abrupt intrathecal withdrawal - risk for rhabdomyolysis CNS depressant GI symptoms (nausea, constipation) Urinary retention
Antipsychotic Agents: Classification by potency
**Low potency - chlorpromazine HCl (Thorazine)** Medium potency - loxapine (Loxitane) **High potency - haloperidol (Haldol)**
Conventional Antipsychotic Agents (FGAs): Individual Agents
All FGAs are equally effective. Differences relate to side effects. High-potency agents produce fewer side effects than the low potency agents. High potency agents produce more early EPS but less sedation, orthostatic hypotension and anticholinergic effects; therefore, high potency agents are generally preferred for initial therapy.
Low-Potency Agents / Anti-Psychotics
*Chlorpromazine (Thorazine): Prototype* Indicated for schizophrenia & other psychotic disorders; PO, IM, IV & rectal suppository; IV/IM peak plasma levels 10 X the equal oral dose Adverse Effects: sedation, orthostatic hypotension, anti-cholinergic effects; neuroendocrine effects; photosensitivity. Risk of EPS low, but risk of TD same as other FGAs. Lowers seizure threshold. Drug Interactions: Can ↑ CNS depressant and anticholinergic drug effects
High-Potency Agents / Anti-Psychotics
*Haloperidol (Haldol): Prototype* Anti-psychotic effects = to chlorpromazine. Principal indications: schizophrenia and acute psychosis. Also preferred agent for Tourette's. Also effective for refractory migraine (not approved.) Adverse Effects: Early EPS (acute dystonia, parkinsonism, akathisia) occur often; but sedation, hypotension, anticholinergic effects are uncommon. Incidence of TD same as with low potency agents. Can prolong QT interval. Use with caution in pts with dysrhythmia risk factors. PO, IM & IM depot preparation
Atypical Antipsychotic Agents (Second Generation Antipsychotics)
Examples: clozapine and other atypical antipsychotics
Other Atypical Antipsychotics
**Risperidone (Risperdal)** Indication: Schizophrenia & bipolar mania Improves positive & negative symptoms & cognitive function Mechanism of action: Binds to multiple receptors Adverse effects: Generally infrequent and mild
Clozapine [Clozaril] (SGA)
Most effective drug for schizophrenia; but can cause agranulocytosis; should be reserved for pts who have not responded to safer alternatives. Mechanism of action Blocks receptors for dopamine and serotonin; also those for norepinephrine (alpha 1), histamine & Ach. Therapeutic use For Schizophrenia & for ↓ suicidal behavior in pts with Schizophrenia Improves positive and negative symptoms Levodopa-induced psychosis in Parkinson Dz pts d/t low/no blockade of striated dopamine receptors
Clozapine [Clozaril] (SGA)
Adverse effects and interactions Sedation; orthostatic hypotension & anticholinergic effects. Agranulocytosis in first 6 mo of tx: need to monitor WBC and ANC & warn pt of risk; warn of early signs of infection (fever, sore throat, fatigue, mucous membrane ulceration); report asap. Weight Gain: obesity, DM, dyslipidemia: monitor weight, waist circumference; monitor lipids. Seizures in 3% of pts; warn re: hazardous activity Diabetes: check fasting blood sugars; inform pts of symptoms of diabetes
Clozapine
Adverse Effects (cont'd) Myocarditis: educate re: symptoms (unexplained fatigue, dyspnea, tachypnea, chest pain, palpitations. If used off-label to tx effects in elderly patients with dementia About double the mortality rate Drug interactions: due to risk of agranulocytosis, no use with other drugs that can suppress bone marrow function (anticancer drugs).
A patient with schizophrenia is prescribed chlorpromazine (Thorazine) oral concentrate. Which of the following discharge instructions should the nurse complete?
B. Avoid direct skin contact with the medication
Which assessment best determines tardive dyskinesia in a patient taking antipsychotic agents?
C. Twisting, writhing, worm-like movements of the tongue and face
Second- generation antipsychotic (SGA)drugs are commonly preferred over first generation antipsychotics (FGA) primarily because they:
A. Are perceived as being more effective
A highly potent antipsychotic differs from low potency drugs in that it:
B. Produces desired effects at low doses
The priority nursing focus for a patient experiencing acute dystonia is:
A. Airway clearance.
Which of these findings, if identified in a patient who has been receiving a neuroleptic antipsychotic, should the nurse report to the prescriber immediately?
D. Sudden, whole-body muscle contractions
Which of the following symptoms of an adverse effect, if identified in a patient who is receiving thioridazine (Mellaril) or haloperidol (Haldol), should the nurse report to the prescriber immediately?
A. Fainting, not associated with sudden position changes.
A patient's daughter has read that clozapine (Clozaril) is the most effective second-generation antipsychotic. Which of the following should the nurse include in the explanation of why this drug is not used until other agents have failed?
B. Clozaril can have an effect on white blood cell production.
Tricyclic Antidepressants (TCAs)
Drugs of first choice for many patients with major depression (**imipramine** and **amitriptyline**)
Selective Serotonin Reuptake Inhibitors (SSRIs)
Fluoxetine (Prozac, Sarafem): Prototype Most widely prescribed SSRI in the U.S.
Selective Serotonin Reuptake Inhibitors (SSRIs)
Pharmacokinetics: highly protein bound (94%); half-life is prolonged - weeks needed for steady state to develop & for washout
Serotonin/Norepinephrine Reuptake Inhibitors (S/NRIs)
These drugs block neuronal reuptake of serotonin and norepinephrine, with minimal effects on other transmitters or receptors. **Venlafaxine (Effexor)**
Monoamine Oxidase Inhibitors
3 Oral Formulations: Isocarboxazid *(Marplan)* Phenelzine *(Nardil)* Tranlcypromine *(Parnate)* 1 Transdermal Patch Formulation *Selegiline* (Ensam)
Monoamine Oxidase Inhibitors
Drug of choice for atypical depression, despite danger.
Monoamine Oxidase Inhibitors / Adverse effects
Hypertensive crisis from dietary tyramine (headache, tachycardia, hypertension, N & V
Monoamine Oxidase Inhibitors / Drug interactions
MAOIs can interact with many drugs to cause potentially disastrous results. Instruct pts to avoid all medication - prescription and OTC drugs- that have not been approved by HCP
Fluoxetine (Prozac) known to cause
Seratonin Syndrome
Atypical Antidepressants
Bupropion (Wellbutrin)
Bupropion (Wellbutrin) -Actions and Uses
Acts as stimulant and suppresses appetite Antidepressant effects begin in 1 to 3 weeks Does not affect serotonergic, cholinergic, or histaminergic transmission Does not cause weight gain Increases sexual desire and pleasure Used for major depressive disorder Used for prevention of seasonal affective disorder (SAD) Approved as an aid to quit smoking
Dopaminergic Agents
Mechanisms of Action: Levodopa: Promotes dopamine synthesis Carbidopa: Blocks destruction of levodopa in periphery Dopamine agonists: Stimulate dopamine receptors directly Selegiline: Inhibits dopamine breakdown by MAO-B Amantadine: Promotes dopamine release; may block DA reuptake COMT inhibitors: Enhance effects of levodopa by blocking its degradation by COMT
Drug Selection: Initial Treatment
Mild symptoms: MAO-B inhibitor -Selegiline and rasagiline More severe symptoms: begin with levodopa (combined with carbidopa) or a dopamine agonist -Levodopa more effective than dopamine agonists, but long-term use carries a higher risk for disabling dyskinesias -Levodopa for improving motor function -Dopamine agonist for drug-induced dyskinesias Management of motor fluctuations - 2 Types -"Off" times (can be reduced with dopamine agonists, COMT inhibitors, and MAO-B inhibitors) -Drug-induced dyskinesias-Amantadine only
Levodopa Therapy
As PD progresses, it becomes more difficult to control it with levodopa Ultimately, levodopa no longer controls the PD, and patient is seriously debilitated This generally occurs between 5 and 10 years after the start of levodopa therapy
Levodopa
Highly effective, but benefits diminish over time -Most effective in first 2 years - by end of 5 years, symptoms may return to pretreatment level **Acute loss of effect and on-off phenomenon** Orally administered, rapid absorption from small intestine -Food delays absorption (slows gastric emptying) -Neutral amino acids compete with levodopa for intestinal absorption and for transport across blood-brain barrier, therefore... **High-protein foods will reduce therapeutic effects**
Levodopa
*Acute Loss of Effect* Gradual loss = "wearing off" Abrupt loss = "on-off" phenomenon
Levodopa
*Gradual loss ("wearing off") - develops near the end of the dosing period - indicates that drug levels have become sub therapeutic -Shorten the dosing interval -Give a drug that prolongs levodopa's half-life (entacapone) -Give a direct-acting dopamine agonist
Levodopa
*Abrupt Loss of Effect -Referred to as the *"on-off" phenomenon* -Can occur at any time during dosing interval (even when drug levels are high) -"Off" times - may last minutes to hours; likely to increase in intensity & frequency over course of TX -Certain drugs are given to help reduce "off" times *Avoiding high-protein meals may help*
Levodopa
*Adverse effects (mostly dose dependent) -Nausea and vomiting -Dyskinesias -Cardiovascular effects - postural hypotension; dysrhythmias d/t excessive stimulation of beta 1 receptors in the heart -Psychosis -May darken sweat and urine - harmless effect -Can activate malignant melanoma Drug "holidays" Drug interactions: **first-generation antipsychotics, MAOIs, anticholinergics, pyridoxine (vitamin B6)** **Food interactions: protein and vitamins with pyridoxine** -Advise pts to spread protein consumption evenly throughout day
Carbidopa (Lodosyn)
*Advantages -No adverse effects of its own -Increases the available levodopa in the CNS and allows for 75% decrease of levodopa dosage; therefore reduces cardiovascular and GI adverse effects -Effects come mainly from levodopa when given in combination **Levodopa/carbidopa (Sinemet, Paracopa)** **Carbidopa alone (Lodosyn)** Switch from levodopa alone to combination -8-hour delay & dose reduction
Dopamine Replacement Drugs
Contraindications: Angle closure glaucoma (can ↑ IOP) [must be used very cautiously; pts with undiagnosed skin conditions as can activate malignant melanoma. Adverse Reactions: Cardiac dysrhythmias, hypotension, chorea, muscle cramps, and GI distress; urinary retention, depression, psychosis, dyskinesias, rhinorrhea
Dopamine Agonists - Bromocriptine, Pramipexole, Ropinirole
First-line drugs for PD Direct activation of dopamine receptors in striatum of brain Drugs of choice for mild or moderate sxs Comparison to levodopa -Less effective than levodopa -Not dependent on enzymatic conversion to be active -Do not compete with dietary proteins -Lower incidence of response failure and less likely to cause dyskinesias, BUT More serious side effects than levodopa - hallucinations, daytime sleepiness, postural hypotension (younger pts) Two types of dopamine agonists -Derivatives of ergot - bromocriptine (Parlodel) -Nonergot derivatives - pramipexole (preferred), ropinirole & others
Ergot Derivative:
Bromocriptine
Bromocriptine
Can activate dopamine receptors to stimulate the production of dopamine. Also inhibits production of prolactin Can be given with Levodopa-carbidopa to reduce dosages of levodopa. -Helps to prolong "on" periods and minimize "off" periods. Cannot be given to pts with ischemic disease (PVD) due to vasoconstrictive properties
Nonergot Dopamine Agonists
Pramipexole (Mirapex) Used alone in early PD and with levodopa in advancing PD Maximal benefits take several weeks to develop Adverse effects (d/t activation of dopamine receptors) -Monotherapy - nausea, dizziness, daytime somnolence, insomnia, constipation, weakness, and hallucinations -Combined - orthostatic hypotension and dyskinesias and increase in hallucinations -Sleep Attacks; and Rare instances of pathologic gambling and other compulsive self-rewarding behaviors
Nonergot Dopamine Agonists
Ropinirole (Requip) -Also used to treat restless legs syndrome -Appears to delay the need for levodopa therapy when given early in disease; can be used as monotherapy or with levodopa. -Adverse Effects: dizziness, GI upset, and somnolence. -Has many P-450 enzyme interactions (see table 16-3.) -For oral use only
Entacapone
*Selective, reversible inhibitor of COMT* *Only for use with levodopa* Inhibits metabolism of levodopa in the intestines and peripheral tissues Prolongs time that levodopa is available to the brain d/t prolonging levodopa's half-life in the blood Increases levodopa availability by inhibiting COMT, which decreases production of levodopa metabolites that compete with levodopa for transport "Wearing-off" delayed and "on" times extended. May also permit a reduction in levodopa dosage Adverse effects - from the increasing levodopa levels & by itself - GI upset, dyskinesias, urine discoloration
Levodopa/Carbidopa/Entacapone
Fixed-dose combinations sold as *Stalevo* More convenient than taking separate doses Costs a little less *Disadvantage* Only available in immediate-release tablets Only available in three strengths Pts who need more flexibility in their regimen, and those who need SR formulations *cannot* be treated with Stalevo
MAO-B Inhibitors
Selective MAOI therapy: MAOIs break down catecholamines in the CNS, primarily the brain. Considered second- and third-line drugs for treatment of PD *Combination with levodopa - can reduce the wearing-off effect, but benefits are modest* **Selegiline (Eldepryl) and Rasagiline (Azilect)** Inhibit dopamine metabolism
Selegiline (Eldepryl, Carbex, Zelapar)
Monotherapy or used with levodopa Modest improvement in motor function Causes selective, irreversible inhibition of type B monoamine oxidase (MAO-B) **Can suppress destruction of dopamine derived from levodopa and prolong the effects of levodopa** May delay neurodegeneration & dz progression (no conclusive proof) *Adverse effects* -Monotherapy - *insomnia; advise pts to take last dose no later than noon; dizziness; dyskinesias, nausea, syncope* **Drug interactions** - levodopa (intensification responses to levodopa-derived dopamine)
Selegiline
Selegiline is a newer, potent, irreversible MAOI that selectively inhibits MAOB Does not elicit the "cheese effect" of the nonselective MAOIs used to treat depression (if 10 mg or less is used) Also avail as Zelapar: oral disintegrating tab for buccal use - ↑ drug absorption. **Rasagiline (Azilect)**, approved 2008, has similar action but is approved for monotherapy of PD
Amantadine [Symmetrel]
A pre-synaptic dopamine release enhancer Developed as an antiviral agent Responses develop rapidly; best used early in dz. Much less profound than with levodopa or the dopamine agonists but can help to control symptoms of dyskinesias Not considered a first-line agent; usually effective 6-12 mos May be helpful for managing dyskinesias caused by levodopa d/t anti-cholinergic properties. Can cause adverse CNS effects (confusion, lightheadedness, anxiety) & blurred vision, urinary retention, dry mouth, nausea, constipation & insomnia
Anti-Cholinergic Drugs
Trihexyphenidyl and Benztropine mesylate (Cogentin) Block receptors for Ach (blockade of muscarinic receptors) Older drugs; less effective than dopamine or dopamine agonists, but better tolerated Second-line therapy for tremor **Can reduce tremor & rigidity and akinesia, but not bradykinesia.** *Avoid use in elderly - confusion, delusions, hallucinations, sedation.* *Abrupt discontinuation of anti-cholinergics may intensify sxs of PD*
Nonmotor Symptoms and Their Management
90% of patients develop nonmotor symptoms (autonomic disturbances, depression, dementia, and psychosis) Depression (50% of pts) -Amitriptyline - only effective drug -TCA -Anticholinergic effects that can exacerbate dementia -Antiadrenergic effects that can exacerbate hypotension
Briefly describe the pathophysiology of Parkinson's Disease?
Too little dopamine (inhibitory neurotransmitter) Relative increase in Ach (excitatory neurotransmitter) Basal ganglia; involved with movement Rx aimed at restoring balance
What are the 2 major concepts of drug action regarding Parkinson's Drugs?
Drugs that replace or restore dopamine Drugs that reduce ACh Meds are not a cure; they are only a treatment
Why can't we just give the person with PD dopamine? What do we give instead?
Dopamine cannot cross the BBB; metabolized by enzymes COMT and type B MAO too quickly Levodopa Levodopa can cross BBB. Converted to dopamine by dopamine producing cells
What enzyme enhances the conversion of levodopa in dopamine? What vitamin is needed to do this?
Decarboxylase Pyridoxine (B6)
Do we want to encourage or discourage high vitamin B6 diets and/or vitamin B6 supplements?
Discourage High B6 would increase dopamine metabolism in the periphery, thus decrease the amount of dopamine able to cross the BBB (where it is needed)
What is meant by the terms: "wearing off" "on-off phenomenon"
Wearing off: effects of the drug (levodopa) have become sub-therapeutic; return of Parkinson symptoms too quickly On-off: effects of drug suddenly wear off, symptoms abruptly return; hours to minutes, unsure of why
What is the advantage of Sinemet over levodopa alone?
Carbidopa prevents peripheral metabolism of levodopa by blocking decarboxylase; thus more levodopa to cross BBB
What are the major side effects of levodopa (Sinemet)?
-Postural hypotension -Dyskinesias (head bobbing, tics, grimacing) -N and V -Dysrhythmias -Psychological disturbances in elderly
What class of drugs should be avoided in pts receiving levodopa, carbidopa?
Cholinergic Agonists (> Ach) Anti-Cholinergics (blocking these receptors can enhance responses to Levodopa) MAOI (hypertensive crisis) Antipsychotic drugs (they block receptors for dopamine) & TCAs Pyridoxine (B6) - (enhances the destruction of levodopa by decarboxylases)
What adjustments to the diet might need to be made for patients taking levodopa and why?
Reduced protein Protein competes with levodopa for entrance across the BBB (limited number of molecules accepted) Newer drugs: not as much as a problem
Contraindication to use of levodopa:
Malignant melanoma (drugs activates neoplasm)
How will you evaluate the effectiveness of therapy with levodopa/carbidopa (Sinemet)?
Assess for improvements in activities of daily living and for reductions in bradykinesia, postural instability, tremor, and rigidity.
What teaching will you provide to pts regarding the management of orthostatic hypotension?
Advise them to sit or lie down if these occur. Advise them to move slowly when assuming an erect position.
Parkinsonism may render self-medication impossible. What intervention can you suggest?
Assist the patient when necessary. Involve family members in medication administration.
A patient taking levodopa plus carbidopa for Parkinson's disease experiences frequent "on-off" episodes (or abrupt loss of effect). The nurse should teach the patient to: A. take the medication on an empty stomach. B. avoid high-protein meals. C. increase intake of vitamin B6. D. discontinue the drug for 10 days (for a "drug holiday")
B. avoid high-protein meals.
A patient is prescribed a dopamine agonist, pramipexole (Mirapex). Which of the following statements made by the patient indicates a need for further teaching? A. "I can take the medication with food to avoid nausea and vomiting." B. "I may experience hallucinations while taking this medication." C. "I should rise slowly to avoid fainting spells." D. "This medication will stop the progression of Parkinson's disease."
D. "This medication will stop the progression of Parkinson's disease.
The "off-on phenomenon" that some patients with Parkinson's disease (PD) experience is best explained as the: 1. need to take a drug holiday to improve response to medications. 2. variable response to levodopa, resulting in periods of good control and periods of poor control of PD symptoms. 3. alternating schedule of medications needed to control PD. 4. fluctuation of emotions that often occurs with PD
2. variable response to levodopa, resulting in periods of good control and periods of poor control of PD symptoms.
The beneficial role of the newer dopamine agonists, such as pramipexole and ropinirole, is that they: 1. appear to delay the start of levodopa therapy. 2. allow for levodopa therapy to begin earlier. 3. improve the patient's tolerance of Parkinsonian symptoms. 4. replace dopamine in the brain
1. appear to delay the start of levodopa therapy
Selegiline (Eldepryl) is a selective MAO-B inhibitor. When taken for Parkinson's disease, patients must avoid tyramine-containing foods. 1. True 2. False
False
Sundowning
Symptoms worse in evening
Diagnosis of Alzheimer's- MRI
atrophy of brain areas
Diagnosis of Alzheimer's- PET
altered patterns in the brain
Diagnosis of Alzheimer's- Cerebrospinal fluid analysis
presence of abnormal proteins
Drug Therapy- Alzheimer's
Goal of treatment is to improve symptoms and reverse cognitive decline. Available drugs cannot do this. At best, available drugs may retard memory loss and cognition & prolong independent function. Five drugs are approved for AD dementia (none very effective)
Five approved drugs for Alzheimer's
Neuronal receptor blocker -Memantine Cholinesterase inhibitors -Donepezil -Galantamine -Rivastigmine -Tacrine
Drug Therapy- Alzheimer's
Cholinesterase inhibitors may delay or slow progression of disease, but will not stop it. 3 drugs are recommended: donepezil, galantamine & rivastigmine. 4th Drug: tacrine to be avoided d/t liver damage Drugs that block cholinergic receptors (1st-generation antihistamines, TCAs, conventional antipsychotics) can reduce responses to cholinesterase inhibitors
Donepezil (Aricept)
An indirect-acting anticholinesterase drug which increases levels of Ach by inhibiting acetylcholinesterase. Treats mild to moderate AD. Adverse Effects: GI upset, drowsiness, insomnia, and muscle cramps. Increases gastric acid, increasing ulcer risk. Drug Interactions: anticholinergics (counteract donepezil effects) and nonsteroidal anti-inflammatory drugs
Memantine (Namenda)
Drug Therapy- Alzheimers First drug in a new class, the NMDA receptor antagonists Indicated for moderate to severe AD; helps to reduce or arrest degenerative cognitive symptoms. Better tolerated than cholinesterase inhibitors; no evidence that more effective/modifies dz process. Effects are likely to be temporary, but still improve quality of life and general functioning in some pts. Adverse effects Hypotension, Dizziness, Headache, Confusion, Constipation. GI Upset, musculoskeletal pain, fatigue and dyspnea
Other Alzheimer's treatments
Vitamin E and selegiline -Studies inconclusive to support effectiveness NSAIDs (ibuprofen, naproxen, ASA) -Not for treatment, but may help prevention or onset delay (long-term use) Estrogen -Women's Health Initiative Memory Study indicates that estrogen poses slight increased risk for developing AD in older women
Other Alzheimer's treatments
Ginkgo biloba -About equal benefits of tacrine without liver damage; anti-inflammatory, antiplatelet, antioxidant, but bleeding risk. Drugs for neuropsychiatric symptoms -Symptoms experienced by 80% of AD patients -Include agitation, aggression, delusions, hallucinations -Risperdone (Risperdal) & olanzapine (Zyprexa) SSRIs for depression (not AD symptoms)
A patient with mild symptoms of Alzheimer's disease is prescribed donepezil (Aricept). Which statement made by the patient indicates a need for further teaching? A. "The drug will improve transmission by neurons in my brain." B. "I may experience stomach upset or diarrhea while taking this drug." C. "I will take the drug every night at bedtime." D. "The drug will stop the damage to the neurons in my brain.
D. "The drug will stop the damage to the neurons in my brain
A patient is concerned about developing Alzheimer's disease. Which of the following drugs may prevent this disease? A. Estrogen B. Acetaminophen (Tylenol) C. Naproxen (Naprosyn) D. Vitamin E
C. Naproxen (Naprosyn)
Multiple Sclerosis
A chronic, inflammatory, autoimmune disorder that damages the myelin sheath of neurons in the CNS
Signs and Symptoms of MS
Symptoms vary depending **on where CNS demyelination occurs and the size of the region of demyelination** Paresthesias Muscle or motor problems Visual impairment Bladder and bowel symptoms Sexual dysfunction Disabling fatigue Emotional lability Depression
Diagnostic Tools for MS
Important diagnostic tools include: MRI CSF testing VEP (visual evoked potential) All three tests help confirm a suspected Dx; none is confirmative by itself.
Drug Therapy for MS
Drug therapy in MS employed to: -Modify the disease process -Treat an acute relapse -Manage symptoms No cure at present. Disease-modifying therapy -Not a cure, but a delay and decrease in intensity and frequency -Immunomodulators (interferon beta, glatiramer acetate and natalizumab); safer, and, Immunosuppressants (mitoxantrone)
Drug Therapy for MS
Relapsing-remitting MS -This type benefits the most from therapy -Treatment should begin as soon as diagnosed and continue indefinitely -All patients (regardless of age) should receive immunomodulators Interferon beta-1a [Avonex] Interferon beta-1a [Rebif] Interferon beta-1b [Betaseron] Glatiramer acetate [Copaxone] Natalizumab [Tysabri
Drug Therapy for MS
Secondary progressive MS -Interferon beta -Mitoxantrone Primary progressive MS -No drugs have shown effectiveness -Promising studies (methotrexate, azathioprine, cyclophosphamide) Progressive-relapsing MS -Mitoxantrone
Drug Therapy for MS
Treating an acute episode (relapse) -Short course of high-dose IV glucocorticoid -IV gamma globulin Drug therapy of symptoms -All four subtypes of MS have the same symptoms, therefore, the drugs used for treatment are the same for all patients, regardless of MS subtype.
Disease Modifying Drugs I: Immunomodulators
5 immunomodulators currently available
Interferon Beta- Therapeutic use
Reduces the frequency and severity of attacks Reduces the number and size of MRI-detectable lesions Delays progression of disability
Interferon Beta- Adverse effects and drug interactions
**Flu-like reactions** Hepatotoxicity Myelosuppression **Injection-site reactions** Depression Neutralizing Antibodies Drug interactions Preparation, dosage, and administration -Dispensed as single use syringes and vials
Glatiramer Acetate (Copaxone)
Therapeutic use -For long-term therapy of relapsing-remitting MS Description and mechanism -Protects myelin by inhibiting immune response to myelin basic protein Adverse effects -Well tolerated Characteristic self-limited post injection reaction - flushing, palpitations, severe chest pain, anxiety, laryngeal constriction, and urticaria - that lasts 15-20 minutes- requires no treatment
Natalizumab (Tysabri)
Therapeutic uses - MS and Crohn's disease Adverse effects - generally well tolerated (headache, fatigue, abdominal discomfort, arthralgia, depression, diarrhea, gastroenteritis, UTI, lower respiratory tract infection)
Disease Modifying Drugs II: Immunosuppressants
Only one approved by the FDA: mitoxantrone
Mitoxanrone
Therapeutic use -Decreases neurologic disability and clinical relapses Mechanism of action -Binds with DNA and inhibits topoisomerase Adverse effects and drug interactions -Myelosuppression -Cardiotoxicity -Fetal harm -Reversible hair loss, injury to GI mucosa, nausea/vomiting, amenorrhea, allergy symptoms, blue-green tint to urine, skin, and sclera
Mitoxantrone- Monitoring summary
Perform complete blood counts at baseline and prior to each dose Perform liver function tests at baseline and prior to each dose Perform a pregnancy test prior to each dose Determine) left ventricular ejection fraction (LVEF) -Prior to the first dose -Prior to all doses once cumulative dose has been reached -Whenever signs of CHF develop
Bipolar Disorder
Formerly known as manic-depressive illness Afflicts an estimated 3.7% of the adult population **Mainstays of therapy are: *****Lithium & valproic acid (Depakene/Depacote) which stabilize mood***** Many pts also receive an antipsychotic med. Some pts also require an antidepressant med. Is a chronic condition that requires lifelong treatment.
Treatment of Bipolar Disorder: Drug Therapy
Types of drugs employed:**3 Major Types** -Mood stabilizers: *Lithium; valproic acid & carbamazepine (2 anti-epileptic drugs)* -Relieve symptoms during manic and depressive episodes -Prevent recurrence of manic and depressive episodes -Do not worsen symptoms of mania or depression; do not accelerate the rate of cycling Antipsychotics: *olanzepine & risperdal* preferred over traditional antipsychotics (Haldol) -Given during severe manic episodes to control sxs; usually in combo with mood stabilizers Antidepressants -Given during depressive episodes; always in combo with mood stabilizers
Mood-Stabilizing Drugs
Can relieve acute manic or depressive episodes; can prevent symptoms from recurring without aggravating mania or depression and without accelerating cycling. Agents used most often are: Lithium: Prototype and antiepileptic drugs: valproic acid and carbamazepine. Note: use of Fish Oil (Omega 3 fatty acids) (If a patient decides to try this, must advise to decrease intake of omega 6 fatty acids, which negate the effects of omega 3s.)
Lithium (Lithonate, Lithotabs)
Pharmacokinetics *Excretion: rapid renal excretion Short half-life; Excreted by the kidneys; use with caution in pts with ......? D/T short half life and low TI, drug must be administered in divided daily doses—No single daily doses must be used!! Sodium levels - lithium excretion reduced when sodium level low: Teach pts to keep Na+ levels normal. Plasma levels: Measurement essential; draw blood in am - 12 hrs after evening dose ***0.8 to 1.4 mEq/L for acute therapy***
Antiepileptic Drugs
***Valproic acid (Depakene, Depakote, Depacon)*** (has replaced lithium of DOC for many) First line tx for BPD ***(Carbamazepine (Tegretol)*** Reduces symptoms during manic & depressive episodes Protects against recurrence of mania and depression Preferred for pts with mixed mania or rapidly cycling BPD Target trough plasma level 4 to 12 mcg/mL Lamotrigine (Lamictal) Indicated for long-term maintenance Can be used alone or in combination
Normal Sodium levels
135-145 mEq/L
Look at creatinine to assess...
Renal Function
A patient with bipolar disorder is taking lithium. Which of the following signs and symptoms exhibited by the patient would indicate lithium toxicity? A. Anuria, increased appetite, and abdominal distention B. Nonproductive cough, increased deep tendon reflexes, and hypertension C. Polydipsia, slurred speech, and fine hand tremors D. Constipation, asterixis, and generalized edema
C. Polydipsia, slurred speech, and fine hand tremors
A patient with bipolar disorder is taking lithium. Which statement made by the patient indicates a need for further teaching? A. "I should take the medication with milk to decrease stomach upset." B. "I will notify my doctor if I feel hyperactive." C. "I should drink at least 8 to 10 glasses of water every day." D. "I will restrict my sodium intake while taking this medication."
D. "I will restrict my sodium intake while taking this medication."
When administering lithium carbonate, which of the following assessments would indicate that therapy has achieved the desired effect? A. Displays a flight of ideas. B. Exhibits pressured speech. C. Sits and watches TV for 8 hours a day. D. Sleeps 8 hours per night.
D. Sleeps 8 hours per night.
A patient has decided to try fish oil to treat her BPD. It is important for this patient to decrease intake of: A. Diary products. B. Processed grains. C. Red meat. D. Vegetable oils.
D. Vegetable oils.
Sedative Hypnotics
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Benzodiazepines
*Drugs of first choice to treat insomnia and anxiety* Also used to induce general anesthesia, and Used to manage seizure disorders, muscle spasm, panic disorder, and withdrawal from alcohol ***Most familiar member - diazepam (Valium)*** ***Most frequently prescribed: lorazepam (Ativan) and alprazolam (Xanax).*** Safer than general CNS depressants, & have a lower potential for abuse Produce less tolerance and physical dependence Fewer drug interactions
Benzodiazepines- Therapeutic uses
Anxiety, Insomnia, Seizure disorders
Benzodiazepines- Adverse Effects
CNS depression (drowsiness, lightheadedness ok when taken for sleep; warn during daytime) Anterograde amnesia/forgetfulness (esp Halcion)
Benzodiazepines- Drug interactions
CNS depressants if combined = profound resp depression, coma & death. P450: no grapefruit juice - will increase effect of benzo
Benzodiazepines- Tolerance and physical dependence
Tolerance -With prolonged use, tolerance develops to some effects but not others; no tolerance to anxiolytic or hypnotic effects; but to antiseizure effects. Pts tolerant to barbiturates, ETOH, and other CNS depressants show some cross-tolerance to benzos. Physical dependence -Can cause physical dependence, but the incidence of substantial dependence is low; except for Xanax
Benzodiazepines- Treatment with flumazenil
Reversal Agent A competitive benzo receptor antagonist Can reverse sedative effects; may not reverse resp depression
Benzodiazepine-Like Drugs (3 are Available)
All three are preferred agents for tx of insomnia. They are not indicated for anxiety. Zolpidem (Ambien) - most widely used. *Sedative-hypnotic with rapid onset *Short-term management of insomnia Zaleplon (Sonata) [No Use of Cimetidine] *New class of hypnotics, pyrazolopyrimidines *Short-term management of insomnia *Prolonged use does not appear to cause tolerance Eszopiclone (Lunesta) *Is the S-isomer of zopiclone *For treating insomnia *No limitation on how long it can be used
A patient is prescribed eszopiclone (Lunesta) for treatment of insomnia. The nurse should teach the patient that the most common adverse effect is: A. respiratory depression. B. bitter aftertaste. C. anterograde amnesia. D. tolerance.
B. bitter aftertaste
A 24-year-old female patient is prescribed triazolam (Halcion) for short-term management of insomnia at home. Which statement made by the patient indicates an understanding of teaching related to this medication? A. "The medication will not alter my breathing." B. "I can safely drink one or two glasses of wine before bedtime." C. "My chance of addiction to this medication is high." D. "I do not need to take precautions while taking this medication during pregnancy.
A. "The medication will not alter my breathing."
Lipid solubility of benzodiazepines: (Select all that apply). A. Causes induction of hepatic metabolizing enzymes B. Decreases the risk that the drug will cause congenital defects. C. Extends plasma half-life. D. Increases absorption. E. Increases distribution to CNS.
D. Increases absorption. E. Increases distribution to CNS. Because it crosses the BBB
The nurse in the emergency department (ED) administers progressive doses of flumazenil (Romazicon) to a patient who has overdosed on a benzodiazepine and alcohol. A nursing priority in this situation is: A. Adequate fluids. B. Monitoring breathing. C. Reducing anxiety. D. Renal function.
B. Monitoring breathing.
The nurse should assess for which symptoms in a patient with a suspected barbiturate overdose? A. Apnea and hyperthermia. B. Bradypnea and constricted pupils. C. Hypertension and hypothermia. D. Hypotension and dilated pupils
B. Bradypnea and constricted pupils.
An elderly patient occasionally uses diphenhydramine (Sominex) for insomnia. A nursing teaching to prevent a very common adverse effect is: A. Increase fiber in the diet. B. Limit fluids. C. Low-fat diet. D. Take medication with food.
A. Increase fiber in the diet.
A patient is prescribed venlafaxine (Effexor XR). If the patient asks the purpose of this medication, the nurse should: A. ask the patient to talk to the healthcare provider. B. refer the patient to the pharmacist. C. tell the patient the medication will decrease anxiety and depression. D. give the patient a pamphlet on anxiety disorders and treatment
C. tell the patient the medication will decrease anxiety and depression.
A patient with obsessive-compulsive disorder is prescribed sertraline (Zoloft). Which statement made by the patient indicates a need for further instruction? A. "I may develop headaches and trouble sleeping." B. "I will be better in approximately 3 weeks." C. "I will take this medication for about a year." D. "I should watch my diet so that I don't gain weight."
B. "I will be better in approximately 3 weeks."
Basic Pharmacology of Alcohol
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