Which is a serious side effect associated with Lotronex?

• A. Headache
• B. Ischemic colitis
• C. Dyspepsia
• D. Constipation

Answer: (B)

Recognizing a serious adverse effect tied to Lotronex involves understanding that ischemic colitis is a potential life-threatening complication of this medication. Lotronex (alosetron) is a 5-HT3 antagonist used for severe IBS with diarrhea in women, but it carries a risk of reduced blood flow to the colon in some patients, leading to ischemic colitis. This is why ischemic colitis is described as a serious side effect: it can require urgent medical evaluation and discontinuation of the drug.

Common, less severe adverse effects like headaches, dyspepsia, or constipation can occur with Lotronex, but they don’t carry the same level of risk as ischemic colitis. Awareness of this serious risk underpins the drug’s restricted use and monitoring, including patient education on warning signs (sudden abdominal pain, bloody stool) and the need to seek prompt care if they occur.