TABLE 371-5 - Possible Drug Interactions with Selective Serotonin Reuptake Inhibitors

Agent	Effect
Monoamine oxidase inhibitors	Serotonin syndrome - absolute contraindication
Serotonergic agonists, e.g., tryptophan, fenfluramine	Potential serotonin syndrome
Drugs that are metabolized by P450 isoenzymes: tricyclics, other SSRIs, antipsychotics, beta blockers, codeine, terfenadine, astemizole, triazolobenzodiazepines, calcium channel blockers	Delayed metabolism resulting in increased blood levels and potential toxicity - possible fatality secondary to QT prolongation with terfenadine or astemizole
Drugs that are bound tightly to plasma proteins, e.g., warfarin	Increased bleeding secondary to displacement
Drugs that inhibit the metabolism of SSRIs by P450 isoenzymes, e.g., quinidine	Increased SSRI side effects

Note: SSRI, selective serotonin reuptake inhibitor.