PSYCH PART 2.docx

[PSYCH PART 2] ANTIDEPRESSANTS The monoamine deficiency hypotheses asserts that depression is caused by the functional insufficiency of monoamine neurotransmitters norepi, serotonin or both. 5 major classes: selective serotonin reuptake inhibitors (SSRIs), serotonin-norepi reuptake inhibitors (SN...

[PSYCH PART 2] ANTIDEPRESSANTS The monoamine deficiency hypotheses asserts that depression is caused by the functional insufficiency of monoamine neurotransmitters norepi, serotonin or both. 5 major classes: selective serotonin reuptake inhibitors (SSRIs), serotonin-norepi reuptake inhibitors (SNRIs), tricyclic antidepressants, monoamine oxidase inhibitors (MAOIs), and atypical antidepressants. Maximal responses may not be seen for 12 weeks. A drug must be taken at least one month without success to consider tx failure Drugs of first choice are SSRIs and SNRIs (bupropion and mirtazapine). TCAs and MAOIs have more adverse effects SSRIs: Others: citalopram, escitalopram, fluvoxamine, paroxetine, and sertraline - Do not cause hypotension, sedation or anticholinergic effects - Fluoxetine causes CNS excitation rather than sedation - AE: sexual dysfunction (can lower dose or take holidays) or a med can be added (bupropion, nefazodone, and mirtazapine). For males sildenafil can be given. Pt may lose weight early on but weight gain later. - s/e: bruxism, vivid dreams, bleeding disorders, and inc perspiration. Birth defects are low - Serotonin syndrome is possible AE 2-72 hours after tx, s/e ams, agitation, confusion, disorientation, anxiety, hallucination, poor concentration, incoordination, etc sympts resolve once drug is stopped. Risk if given with MAOIs. Taper! MAOIs - increases 5-HT availability Increased risk of serotonin syndrome. - should be stopped 2 weeks prior to starting SSRIs and SSRIS stop 5 weeks prior to MAOI. - Admin orally - Fluoxetine can elevate plasma levels of TCAs and lithium. Highly protein bound and can displace warfarin. Increase risk of bleeding - Reserved for pts that have nor responded to other meds due to hazards - Choice for atypical depression: isocarboxazid, phenelzine, and tranylcypromine - \*\*\*HTN crisis triggered by foods rich in tyramine - Do not dispense to those that cannot follow dietary restrictions - Tx: vasodilators (nitro, phentolamine, and labetalol) - Selegilin - Transdermal. Bypasses first pass effect so preserves MAO-A in intestines low risk w/tyramine foods - AE: rash - Contra: carbamazepine and oxcarbazepine raise levels of selegilin SNRIs- venlafaxine, desenlafaxine, duloxetine, levomilnacipran, milnacipran - Milnacipran - Tx fibromyalgia and sleep - Duloxetine - Off label for chemo neuropathy, stress urinary incontinence - Desvenlafaxine approved for adults. - Off label for hot flashes for menopause - Weight gain - Venlafaxine - Blocks NE and 5-HT - Fetal w/draw in late pregnancy, suicide in young. - MAOIs should be w/drawn 14 days before starting. Venlafaxine should be dc'd 7 days before starting MAOI AE: insomnia, wt loss, diastolic HTN, sexual dysfunction. Hyponatremia in geriatric. TCA - Block reuptake of two monoamine transmitters, NE, and serotonin - AE: sedation, orthostatic hypotension and anticholinergic effect, **cardiac toxicity** - Lethal if OD bicarb for dysrhythmias - Long halflives single daily dose - TCA w/ MAOI sev HTN - If sedation is warranted doxepin - If it's not desipramine - Elderly sensitive to anticholinergic effects nortiptyline OTHER DRUGS - Buproprion (atypical) - Weight loss, Increases sexual desire can be used w/SSRIs - Uses: major depressive disorder and prevention of seasonal affective disorder, stop smoking - AE: seizures avoid doses above 450mg/day, rapid dosage titration, pts with seizure RF, anorexia and drugs that inhibit CYP (increases bupropion levels) - Interactions: sertraline, fluoxetine, paroxentine and MAOIs - Mirtazapine - Blocks histamine receptors promotes sedation and weight gain - AE: somnolence [Postpartum depression] Fluoxetine, sertraline, and venlafaxine. SSRIs are first choice: tolerated and low risk for toxicity with OD Prevent relapse tx should continue at least 6mo Sertraline is the safest for breastfeeding Brexanolone: first FDA approved option for PPD, but infused over 60 hours in hospital.