CNS PART 1 Flashcards
(45 cards)
NSAIDS for migraines
OTC, Rapid onset, useful in early migraines
-Marked lack of potency for most migraine headaches
-Must be taken early in the migraine attack; delayed administration of these drugs will be ineffective.
Acetaminophen
blocks the synthesis of prostaglandins in the brain
- Has analgesic effect for some migraine headaches if used early in the attack.
- Food does not inhibit oral absorption
- No “cross-sensitivity” with aspirin or the NSAIDs
Hepatotoxicity; especially in patients with pre-existing liver disease. Contraindicated in patients with severe liver dysfunction (i.e., cirrhosis)
- Precautions in patients with renal disease; does have some nephrotoxicity
- Must be taken early in the attack to be effective at all
-NSAIDS are more potent
Aspirin-Caffeine-Butalbital (Fiorinal)
-Very rapid onset of action; 15-30 minutes
-three drugs provides greater potency for migraine relief than the aspirin, NSAIDs, or acetaminophen do alone
-schedule III drug
-Contraindicated in pregnancy; barbiturates are teratogenic
-Precaution in pts with resp diseases
-Risk for addiction, causes hangover effect, contains ASA
Serotonin Agonists;
ergotamine (Ergomar)
long track record of success
-Rapid onset
-sup, sublingual, supp, inhaled
-Can be effective for mild, moderate, and some severe migraine headaches
-Can cause physical dependence- rebound headache
-Most effective if used early
- May cause peripheral vasospasm
- Contraindicated in patients with peripheral vascular disease, coronary occlusive disease, hypertension, or severe renal or hepatic disease
- no for pregos; they cause uterine contractions
- Contraindicated with several drugs;antifungals (such as itraconazole), erythromycin-type antibiotics and HIV protease inhibitors
- Precaution required in children
Serotonin Agonists;DIHYDROERGOTAMINE
-IV, IM ,spray for nausea
-rapid onset
-No risk of physical dependence or abuse
- Causes less nausea and peripheral vasospasm than ergotamine
- May be effective in some patients who do not respond to triptans
-Same contraindications as ergotamine
- Effectiveness decreases the later in the attack the drug is administered
- Not available orally
- Can cause -numbness of the fingers and toes, muscle aches, tachycardia or bradycardia, increase or decrease in blood pressure
Serotonin Agonists; SUMATRIPTAN and the other “Triptans”
- Most effective of all the anti-migraine medications
- Cerebral vasoconstriction is the predominant effect; less peripheral vasoconstriction
- Less nausea
- Still effective if administered late in the attack
- Minimal CNS sedation;
Can be used (with precaution) in pregnancy
Use limited per 24 hrs - Commonly causes tightness in the chest, jaw, and neck; also causes a warm, tingling sensation
- Contraindicated in coronary artery disease, ischemic heart disease, or angina
-May cause dizziness, drowsiness and fatigue
Adjunctive Drugs for the Abortive Treatment of Migraine
Antimedics- metoclopramide (Reglan), prochlorperazine (Compazine), promethazine (Phenergan)
sedatives- butalbital (as in Fiorinal)
narcotics - meperidine (Demerol),codeine (various combinations), butorphanol (Stadol)
Prophylactic Drugs Used for Migraine
Tricyclic Antidepressants
- amitriptyline (Elavil)
Beta Blockers
- propranolol (Inderal)
- atenolol (Tenormin)
Anticonvulsants
- divalproex/valproate (Depakote)
- topiramate (Topamax)
SSRI’s
- fluoxetine (Prozac)
- sertraline (Zoloft)
Monoamine Oxidase Inhibitors
- phenelzine (Nardil)
Calcium Channel Blockers
- nimodipine (Nimotop)
- verapamil (Calan
Calcitonin Gene-Related Peptide (CGRP) Receptor Antagonists- new migraine med
Additional option for prophylaxis for those currently not controlled on more traditional prophylactic medications. (Aimovig, Ajovy, Emgality, Vyepti)
-Convenient dosing depending on the drug
-Ubrelvy offers another option for abortive therapy
Expensive
- Antibody development (humanized monoclonal antibody)
-Injection site reactions (for those that are not oral)
new Serotonin Agonists-lasmiditan (Reyvow)
Acute TREATMENT med-PO
- Can only take one dose (suppose migraine doesn’t go away?)
-Warnings for driving impairment, CNS depression, Serotonin syndrome, medication overuse headache.
PARKINSONS MEDS
Dopamine Agonists (including inhaled versions), Anticholinergics, Monoamine Oxidase B Inhibitors, COMT Inhibitors, and adenosine receptor antagonists.
DOPAMINE AGONIST DRUGS
For Parkinson’s Disease
amantadine (Symmetrel) (Gocovri) (Osmolex ER)
bromocriptine (Parlodel)
levodopa-carbidopa (Sinemet)
pramipexole (Mirapex)
ropinirole (Requip)
-They mimic actions of dopamine; replace in the brain what the brain is lacking which comes close to a specific correction of the basic pathophysiology.
-useful as monotherapy
-Most require BID to QID dosing
Most require frequent titration of doses; exact dose difficult to establish and it constantly changes
- Most are relatively expensive
- Commonly produce hallucinations
DOPAMINE AGONIST DRUGS
LEVODOPA-CARBIDOPA, LEVODOPA
Levodopa is metabolized into dopamine; carbidopa blocks an enzyme responsible for the peripheral (non-brain) metabolism of levodopa
-. Available in sustained-release
-Only small amounts actually enter the brain because of extensive peripheral metabolism before the drug can get across the blood brain barrier
-over 50% of patients) causes involuntary skeletal muscle movements
May cause orthostatic hypotension
- Can cause a variety of CNS adverse effects; inattention, memory loss, agitation, anxiety, confusion, depression, delirium, inappropriate or excessive sexual behavior, etc.
- Can cause visual problems; blurring, miosis, mydriasis, staring
-May cause excessive nasal discharge
- In general, has a narrow margin of safety.
- Contraindicated in glaucoma and in cases of suspected melanoma; levodopa can stimulate the growth rate of melanoma.
DOPAMINE AGONIST DRUGS-CONT LEVODOPA-CARBIDOPA DISADVANTAGES
less peripheral conversion before entry into the brain.
- Tolerance possible with continuous use
Commonly associated with an “On-Off” Phenomenon; relatively rapid fluctuations (within hours) of poor control of bradykinesia with period of dyskinesia (i.e., periods of muscle rigidity fluctuating with period of involuntary excessive muscle activity
DOPAMINE AGONIST DRUGS-BROMOCRIPTINE
Adjunctive benefit when given concurrently with levodopa-carbidopa; allows a reduction in the dose
- Prevents fluctuations in the patient’s response to levodopa-carbidopa
- May cause drowsiness and headache, and Nausea
- Possible hypotension (orthostatic);in older adults
- Not useful as monotherapy; only effective when used as an adjunct to levodopa - carbidopa
DOPAMINE AGONIST DRUGS-AMANTADINE
Stimulates the release of the body’s natural dopamine from the remaining dopamine-producing neurons; a direct correction of the basic pathophysiology of the disease.
- Dual therapeutic actions; useful as a dopamine agonist in Parkinson’s Disease and, by a different pharmacodynamic mechanism, as an anti-viral agent in influenza.
- No specific contraindications.
- Useful as initial monotherapy; can reduce bradykinesia effectively by itself in many early cases of the disease.
-Has anticholinergic adverse effects, lack potency,
- May cause dizziness, insomnia, ataxia, confusion
- Has a beneficial psychotomimetic effect; improves mood and sense of well-being in Parkinson’s patients
- Minimal adverse effects-Not metabolized
Anticholinergic Drugs: benztropine (Cogentin)
trihexyphenidyl (Artane)
decrease acetylcholine, to balance out the production of dopamine and acetylcholine.
Most useful for the treatment of Parkinsonian tremor; no effect on bradykinesia
- Has anticholinergic effect of producing dry mouth
- Inexpensive
- Useful as adjuncts to the dopamine agonist drugs
- Can be used as initial monotherapy
- Not effective for the bradykinesia or muscle rigidity of Parkinson’s Disease
- Use of these drugs is usually limited to early Parkinsonism; lack potency for severe, advanced cases.
- Contraindicated in glaucoma.
MAO-B Inhibitors-IRREVERSIBLY BOUND
rasagiline (Azilect)
selegiline (Eldepryl) (Deprenyl) (Zelapar)
-May delay the progression of Parkinson’s Disease
-Useful as an adjunct to the dopamine agonist drug
-Not effective as monotherapy
-Cause nausea
- May cause nervousness and anxiety; these are effects of the amphetamine metabolites
- May rarely cause abdominal pain, dry mouth, insomnia, hallucinations, dyskinesias, mood swings.
MAO-B Inhibitors – REVERSIBLY BOUND
safinamide (Xadago)
Specifically approved by the FDA for the adjunctive treatment with levodopa/carbidopa in patients with Parkinson’s disease experiencing OFF episodes.
-not effective as monotherapy.
- contraindicated in severe hepatic impairment and when administered with any other MAO inhibitor, opioids, (SNRIs), tricyclic, tetracyclic, or triazolopyridine antidepressants, cyclobenzaprine, methylphenidate, amphetamine derivatives, St. John’s Wort, and dextromethorpha
COMT Inhibitors;
entacapone (Comtan)
tolcapone (Tasmar)
- Not useful as monotherapy; only effective when given as an adjunct to levodopa - carbidopa.
Tolcapone can cause liver failure; its use is limited to those patients who have exhausted other treatment options. If no benefit is evident within 3 weeks of initiating treatment the drug should be withdrawn. - Can cause diarrhea, orthostatic hypotension and hallucinations.
inhaled Dopamine Agonists-Levodopa (Inbrija)
Specifically FDA approved for the intermittent treatment of OFF episodes of Parkinson’s disease in patients treated with carbidopa/levodopa (not approved as monotherapy)
-Need to take upwards of 5 times daily
-Not effective as monotherapy
Adenosine Receptor Antagonists-istradefylline (Nourianz)
-Specifically FDA approved for adjunctive therapy with carbidopa/levodopa in patients with Parkinson’s disease experiencing OFF episodes.
-expensive $2,000 per month
-Can’t be used as monotherapy.
Drugs Used to Treat Epilepsy
phenytoin (Dilantin)
carbamazepine (Tegretol)
oxcarbazepine (Trileptal) (Oxtellar XR)
ethosuximide (Zarontin)
divalproex sodium (Depakote)
valproate (Depakene)
lamotrigine (Lamictal)
phenobarbital (Luminal)
topiramate (Topamax)
rufinamide (Banzel)
Phenytoin (Dilantin)
-Effective in partial and generalized tonic-clonic seizures
-Least sedating drug to treat seizures of any type.
- May cause a variety of CNS adverse reactions; dizziness, ataxia, slurred speech, confusion, insomnia, nystagmus.
- Can produce a rash
-Cannot be abruptly discontinued
- Totally ineffective for absence seizures
Long-term therapy can produce cosmetic problems; acne, hirsutism, coarsening of facial features, gingival hyperplasia
- Can produce lymphadenopathy
- Can cause hyperglycemia
- Teratogenic in pregnancy (Pregnancy category D)
- Narrow therapeutic window
-Baseline CBC, urinalysis and liver function tests should be complete prior to beginning therapy.
