Antidepressants Flashcards
Amitriptyline Brand Name
Elavil
Amitriptyline Indication/Dosage
Relief of depression symptoms: 40-150mg/day in divided doses or at HS
Amitriptyline mechanism
inhibits membrane pump mechanism responsible for reuptake of NE and 5-HT at presynaptic nerve terminals, potentiating activity at postsynaptic terminals
One of the more sedative TCA’s
Onset may take up to 30 days
Amitriptyline Drug Interactions
may increase action of dicumarol
may decrease effectiveness of clonidine and guanethidine
fluoxetine: may increase toxicity
may increase effects of direct-acting sympathomimetics
MAO-I’s: may produce toxic effects when used together!
alcohol and other CNS depressants: increased CNS depression
cimetidine: increased Amitriptyline plasma concentrations
Amitriptyline CI’s/precautions
CI: patients currently or within past 14 days taking MAO-I, and during acute recovery phase following MI
caution: pregnancy, impaired liver function, angle-closure glaucoma, urinary retention, increased intraocular pressure, epilepsy, CV disorders, and hyperthyroidism
Amitriptyline Pregnancy Category
C
Amitriptyline ADR’s
Tachycardia, dry mouth, blurred vision, N/V, dizziness, weakness, headache, constipation, urinary retention, drowsiness, weight gain
Amitriptyline Patient Educaion
do not discontinue unless otherwise directed
caution when operating machinery or when mental alertness required
avoid alcohol
Bupropion brand names
Wellbutrin, Forfivo XL, Zyban
Bupropion indications/dosages
treat depression and prevent SAD episodes: ER 150-300mg daily.
IR: start at 100mg BID, increase by no more than 100mg/day at minimum 3 day intervals. usual dose is 100mg TID, max dose is 450mg/day (as 150mg TID)
SR: up to 400mg/day in 2 doses, target dose is 300mg/day
SMOKING CESSATION: (Zyban) 150mg/day for 3 days, then increase to 150mg BID
Bupropion mechanism
dose-related CNS stimulant effect
weak inhibitor of neuronal uptake of NE and DA, does not inhibit MAO
mediated by noradrenergic and/or dopaminergic mechanisms
Bupropion metabolism and excretion
metabolized by 2B6 in liver to active metabolites
excreted in urine and feces
up to 80% protein bound
Bupropion drug interactions
MAO-Is and L-dopa increase toxicity effects
alcohol may lower seizure threshold
drugs that affect 2B6 enzyme (orphenadrine, thiotepa, cyclophosphamide, ticlopidine) may affect plasma levels of Bupropion
ritonavir and lopinavir: reduce plasma levels
Bupropion inhibits 2D6 and may increase plasma levels of TCA’s, paroxetine, fluoxetine, sertraline, Haldol, Risperdal, thioridazine, metoprolol, propafenone, and flecainide
Bupropion CI/precautions
CI: seizure disorder, history of bulimia or anorexia nervosa, MAO-I use in past 14 days.
may increase suicidal thoughts/actions
May lower seizure threshold (10x higher between 450mg and 600mg/day)
psychomotor disturbances may be seen, such as mania, psychosis, and hallucinations
Caution in liver or kidney dysfunction
Bupropion pregnancy category
C
Bupropion ADRs
dizziness, constipation, weight loss, dry mouth, insomnia, sweating, agitation, tremor
Bupropion patient education
IR should be taken at regular intervals ER should be taken in AM to avoid insomnia swallow SR and XL tabs whole! consult pharmacist for OTC meds refrain from alcohol weight loss or gain may be temporary pay close attention to mental changes may take ~2 weeks to show improvement, full benefit seen around 2 months
Citalopram brand name
Celexa
Citalopram indication/dosage
treatment of depression: begin with 20mg daily, gradually increasing to 40mg daily
Citalopram mechanism
blocks neuronal uptake of 5-HT, but not NE or DA
much less potent binding to muscarinic, histaminergic, and alpha-receptors than classical TCAs
Citalopram metabolism
CYP3A4 and 2C19
Citalopram drug interactions
coadmin with MAO-Is may produce serious reactions resembling NMS
inhibitors of 3A4 have NO EFFECT on plasma clearance
cimetidine increases plasma levels
coadmin with aspirin or NSAIDs may increase risk of GI bleeding
Citalopram CI/precautions
Antidepressants may increase suicidal thoughts/actions
CI: MAO-I use in past 14 days
caution when dispensing large quantities of medication
caution in liver disease
Citalopram pregnancy category
C
caution during nursing
Citalopram ADRs
nausea, dry mouth, somnolence, insomnia, diarrhea, ejaculation disorders, and impotense
abrupt discontinuation may cause adverse effects including dysphoric mood, irritability, agitation, dizziness, anxiety, confusion, insomnia, and headache
Citalopram patient education
may impair cognitive and motor performance
may take 2-4 weeks to see effects
do not abruptly discontinue
avoid alcohol
pay attention to mood or mental changes, let those close to you know.
