antidepressants Flashcards
Citalopram (celexa) p450 metabolism?
Substrate 2c19 major
Adverse effects of citalopram?
QTc prolongation warning ekg for doses greater than or equal to 40 MG daily or patients with CV risk ; lower dose with strong 2c19 inhibitors
Escitalopram (lexapro) dosing adjustments?
Lower doses for patients taking strong 2c19 or 3 A4 inhibitors
What is the p450 metabolism of fluoxetine?
Substrate 2c9,2d6 (mjor) inhibitor: 1A2, 2C19, (moderate) 2d6 (strong)
Norfluoxetine:inhibitor 3A4 (strong)
What is the half life of fluoxetine?
7-9 days.
How should you adjust fluoxetine for hepatic impairment?
Half the dose
Fluvoxamine is what p450 metabolizer?
Strong 1A2, 2C19 inhibitor
What is the most common use for Fluvoxamine?
OCD
What is the P450 metabolism of Paroxetine?
Strong 2D6 inhibitor
What must be done when going off of paroxetine, even if switching to another antidepressant?
Must taper dose due to anticholinergic effects. This will help avoid the cholinergic rebound, even if switching to another antidepressant.
What pregnancy category is Paroxetine? Why?
Category D. Septal wall defects.
What is the P450 metabolism of Vilazadone (Viibryd)?
MAjor 3A4. Must reduce target dose to 20mg once daily when given with strong 3A4 inhibitors. Avoid use with stron 3A4 inducers. Give with food to improve absorption.
Vortioxetine (Brintellix) - SSRI: What type of metabolism is this and how should the dose be adjusted because of this?
Major 2D6 substrate. Reduce target dose to 10mg daily with strong 2D6 inhibitors or in patients that are poor 2D6 metabolizers.
Which antidepressants are SSRI’s?
Citalopram, escitalopram, Fluoxetine, Fluvoxamine, Paroxetine HCl, Sertraline, Vilazodone, and Vortioxetine.
Which antidepressants are SNRI’s?
Desvenlafaxine, Duloxetine, Levomilnacipran, Milnacipran, Venlafaxine, Buproprion, Mirtazapine, Trazodone
Desvenlafaxine is what type of P450 metabolizer?
NO significant interactions
Why is it difficult for patients to reach the target dose of Desvenlafaxine?
Significant nausea, most only reach 100mg daily instead of 400mg daily. CrCl
Duloxetine(Cymbalta) is what P450 metabolizer?
Major 2D6 inhibitor
What is the most limiting side effect of Duloxetine?
Nausea
What is the rule for Levomilnacipran for patients with renal impairment?
Do not exceed 80mg once daily in these patients or in patients on strong 3A4 inhibitors. Max of 40mg/day in severe renal impairement
What is Milnacipran (Savella) FDA approved for treating?
Only for fibromyalgia. No dosing requirements for Depression.
Venlafaxine is metabolized by what P450 enzyme? How does this impact dosing?
2D6, and 3A4 (major). Consider dose reduction if given with inhibitors of either of these.
Buproprion HCl should be avoided in what patients?
Active seizure disorders and eating disorders
Buproprion HCL is what P450 substrate?
2B6
What is a major side effect of Mirtazipine?
Sedation and appetite increase occur with doses less than or equal to 15mg/day.
What is the P450 metabolism of Trazadone?
major 3A4 Substrate, moderate 2D6 inhibitor
What is the primary clinical indication of Trazadone?
insomnia at a dose range of 50mg - 150mg at bedtime
What medications are TCAs?
Amitriptyline, Desipramine, Imipramine, Nortriptyline
Amitriptyline is commonly used for what indication other than depression? what is the dose adjustment for this?
Neuropathic pain at lower doses (25 - 100mg at bedtime)
Which TCA is not commonly used for depression?
Desipramine
What is the most common clinical indication for Imipramine?
Mostly for children with ADHD or nocturnal enuresis at lower doses of 10 - 25mg daily.
Other than depression, what can Nortriptyline be used for?
Smoking Cessation
Which medications are MAOI’s?
Isocaroxazid, Phenelzine, Selegiline, and Tranylcypromine
What are all MAOI’s indicated for and what is important to know when switching to this from another antidepressant?
Indicated for monotherapy only!! Must have a 2 wk washout of other antidepressants. 4 to 5 wks for fluoxetine.
What is important to know about Selegiline patches?
6mg/24 hour patch does not require tyramine diet. other patch strengths do!!
