Some of my patients on 5-HT3 antagonists (eg, ondansetron [Zofran], granisetron [Kytril], palonosetron [Aloxi], others) complain that the side effects prevent them from taking these medications as prescribed. How should these be managed so patients can take their antiemetic prophylaxis? — Name withheld on request

Two of the most common adverse effects of the 5-HT3 antagonists include constipation and headaches. Constipation may occur with all agents in this class, including ones administered through a nonoral route (ie, parenteral or topical). It occurs more frequently with higher doses of these agents.

Related Articles

Management should consist of proactive strategies, including adequate water and fiber intake, and considering use of stool softeners or stimulant laxatives as needed.

Headaches may be managed using acetaminophen or NSAIDs (eg, ibuprofen [Motrin, Advil], naproxen [Aleve]) as appropriate. Switching between 5-HT3 antagonists is typically effective to prevent future headaches.