What notable side effect is associated with SNRIs such as venlafaxine?

• A. Sedation and ataxia
• B. Photosensitivity and rash
• C. Hypertension and dose-related increases in blood pressure
• D. Weight gain and sexual dysfunction

Answer: (C)

SNRIs increase norepinephrine signaling by blocking its reuptake, and venlafaxine’s effect on the norepinephrine system becomes more pronounced at higher doses. This can lead to vasoconstriction and higher peripheral vascular resistance, producing an increase in blood pressure that tends to rise in a dose-related fashion. Because of this, hypertension is a notable and clinically important side effect to monitor during treatment, especially at higher doses or in patients with preexisting high blood pressure. Regular blood pressure checks help guide dosing decisions and can prompt adjustments if significant elevations occur.

Sedation and ataxia aren’t typical hallmark effects of SNRIs. Photosensitivity and rash aren’t characteristic side effects of this class, though individual responses can vary. Weight gain and sexual dysfunction can occur with SNRIs, but the most distinctive and dose-dependent cardiovascular effect to watch for is elevated blood pressure.