Chapter 35: Antidepressants Flashcards
(7 cards)
What signs and symptoms indicate increased suicide risk in individuals taking antidepressants, and how can the risk be reduced?
Watch for suicidal thoughts, worsening mood, and behavioral changes—especially early in treatment.
Risk is reduced by close monitoring, limiting prescription quantities, and observing inpatient dosing.
Compare the mechanisms of TCAs, SSRIs, SNRIs, and MAOIs.
- TCAs: Block NE and serotonin reuptake.
- SSRIs: Selectively block serotonin reuptake.
- SNRIs: Block serotonin and NE reuptake; weak dopamine effect.
- MAOIs: Inhibit MAO enzyme, preventing breakdown of NE, serotonin, and dopamine.
Compare the main adverse effects of TCAs, SSRIs, SNRIs, and MAOIs.
- TCAs: Sedation, orthostatic hypotension, anticholinergic effects, cardiac toxicity.
- SSRIs: Nausea, insomnia, sexual dysfunction, serotonin syndrome.
- SNRIs: Similar to SSRIs + diastolic hypertension.
- MAOIs: CNS stimulation, orthostatic hypotension, hypertensive crisis with tyramine.
What is the stepwise pharmacologic approach to treating depression with TCAs, SSRIs, SNRIs, and MAOIs?
SSRIs and SNRIs are first-line due to safety and tolerability. TCAs are second-line, used for resistant cases or neuropathic pain. MAOIs are last-resort due to dietary/drug interaction risks—used for atypical depression.
How do MAOIs cause hypertensive crisis from dietary tyramine?
MAOIs block breakdown of tyramine in the gut, allowing tyramine to enter circulation, trigger massive NE release, and cause dangerous vasoconstriction and cardiac stimulation.
What should patients taking MAOIs be educated about regarding hypertensive crisis?
Avoid tyramine-rich foods (e.g., aged cheese, cured meats); know signs like severe headache, hypertension, nausea, confusion, and sweating; and be aware of serious drug interactions.
How is hypertensive crisis from MAOIs treated?
It’s a medical emergency. Treat with IV vasodilators: sodium nitroprusside, phentolamine, or labetalol.
