SSRIsSNRIs

SSRIs and SNRIs are two related classes of antidepressants that modulate brain neurotransmitters to treat mood and anxiety disorders. SSRIs selectively inhibit the reuptake of serotonin, increasing its availability in the synapse. SNRIs inhibit reuptake of both serotonin and norepinephrine, which can enhance mood and pain control for some patients.

Common SSRIs include fluoxetine, sertraline, citalopram, escitalopram, fluvoxamine, and paroxetine. Common SNRIs include venlafaxine, duloxetine, desvenlafaxine, and milnacipran. These medications are approved for major depressive disorder and several anxiety disorders; duloxetine and milnacipran are also used for certain chronic pain conditions. Onset of benefit typically requires several weeks of treatment.

Adverse effects are usually mild to moderate and can include nausea, diarrhea, sleep disturbance, headache, and sexual dysfunction. Weight changes may occur, and some SNRIs can raise blood pressure at higher doses. Hyponatremia risk exists, particularly in older adults. A discontinuation syndrome can occur with abrupt stopping, so gradual tapering is recommended. Serotonin syndrome is a rare but serious risk when these agents are combined with other serotonergic drugs.

Considerations include monitoring for mood symptoms, suicidality, blood pressure, and interaction with other medications such as monoamine oxidase inhibitors. Use in pregnancy requires careful risk-benefit assessment. Overall, response to SSRIs and SNRIs is individualized, and treatment is tailored to the patient’s symptoms and tolerability.