In this episode, we review the pharmacology, indications, adverse effects, and unique drug characteristics of the most common SSRIs on the market. Key Concepts SSRIs (selective serotonin reuptake inhibitors) are the drug of choice for depression, anxiety, and a variety of other psychiatric indications. Fluoxetine (Prozac) and paroxetine (Paxil) inhibit CYP2D6, a metabolic pathway for several opioid analgesics, tamoxifen, and many other antidepressants. Adverse effects of SSRIs start immediately but the beneficial psychiatric effects take up to 1 to 2 months to occur. Patient counseling about the timing of adverse effects and efficacy are important! SSRIs should not be abruptly discontinued in patients taking the medication chronically. Withdrawal symptoms can include flu-like symptoms, changes in mood or sleep, and (rarely) even electric-like shocks. To discontinue, the SSRI dose should be tapered down over the period of several weeks.