week 1 flashcards

agonist at 5HT-1B and 5HT-1D receptors, result in vasoconstriciton. presynaptically, agonism at these receptors. also inhibits the release of neurotransmitters that activate pain fibers.

sumatriptan fastest, reaches peak plasma concentrations 12 min p SC. frovatriptan/naratriptan longest acting (slowest onset). sumatriptan/zolmitriptan also available as nasal sprays (nausea/vomiting).

metabolism often by MAO-A (frovatriptan CYP1A2, eletriptan CYP3A4 / PGP).

CAD, uncontrolled HTN, MAOI use within 14 days.

triptan + triptan (additive). triptan + ergot w/i 24h. triptan + MAOI w/i 14d. rizatriptan + propranolol (reduce dose).

migraines (abortive), cluster headaches (abortive). longer-acting formulations may be used for prevention of menstrual migraines.

paresthesias, chest/jaw/neck tightness/pain/pressure, hypertension.

can typically repeat dose, but there is a max dose per 24 hours. adjust doses in hepatic impariment (metabolized by liver). if one triptan doesn't work, try another.

almotriptan (triptan)

eletriptan (triptan)

frovatriptan (triptan)

naratriptan (triptan)

rizatriptan (triptan)

sumatriptan (triptan)

zolmitriptan (triptan)

1. drug that increases GABA activity, 2. drug that vasoconstricts, 3. drug that is a CNS depressor

topiramate (AED - miscellaneous)

unknown, likely has multiple mechanisms including Na or Ca channel blocking, GABA potentiation, NMDA antagonism, or inhibition of carbonic anhydrase.

migraines (prophylaxis), seizure disorders (broad-spectrum)

TAPER UP, TAPER DOWN. will require dosing adjustments in hepatic/renal disease.

significant cognitive impairment, fatigue, paresthesias, taste changes, weight loss.

do NOT need to monitor levels (newer AED)

pregnancy (cat D, cleft palate in 1st trimester)

topiramate + OCPs (decreased levels of OCP), topiramate + other AEDs (multiple interactions due to induction/inhibition of hepatic enzymes)

phenytoin (AED - hydantoin)

seizure disorders (broad-spectrum but not absence seizures), status epilepticus (2nd line)

sodium channel inhibitor, slows their recovery from an inactivated state (preventing repetitive firing). selectively targets channels that are opening/closing rapidly. (may also be other mechanisms)

exhibits saturation kinetics: at low concentrations first order kinetics, at high concentrations zero order kineti H highly protein bound.

TAPER UP, TAPER DOWN. ER formulations contain 8% less drug than IR (monitor closely when switching).

phenytoin + OCPs (decreased levels of OCP), phenytoin + other AEDs (multiple interactions due to induction/inhibition of hepatic enzymes). may also saturate pathways used by other drugs.

DO need to monitor levels (older AED)

pregnancy (cat D, fetal hydantoin syndrome), bradycardias/certain arrhythmias

BBW for cardiovascular risk with rapid infusion. gingival hyperplasia (regular dental exams), coarsening of facial features in women. lateral gaze nystagmus.

prodrug, dosed in phenytoin equivalents (PE) to avoid need for conversion. it is better tolerated, safer, and leads to quicker therapeutic levels but is more expensive.

lamotrigine (AED - phenyltriazine)

sodium channel inhibitor, slows their recovery from an inactivated state (preventing repetitive firing). may also inhibit Ca channels and glutamate release.

seizure disorders (broad-spectrum), bipolar disorder

only available orally (but has multiple oral forms). can produce auto-induction at higher doses.

do NOT need to monitor levels (newer AED)

BBW for serious rash (SJS). discontinue at first sign of unexplainable rash.

lamotrigine + OCPs (decrease levels of lamotrigine). lamotrigine + other AEDs (multiple interactions due to induction/inhibition of hepatic enzymes)

okay-ish in pregnancy (cat C)

TAPER UP, TAPER DOWN. will require dosing adjustments in hepatic/renal disease. phenytoin, carbamazepine, and phenobarb reduce lamotrigine levels; valproate increases levels.