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Short answer Pregnancy and alosetron: what to know Common questions Related questions Sources**Alosetron is not a first choice in pregnancy, and most clinicians stop it or replace it once you know you are pregnant.**
Alosetron is a prescription drug for severe diarrhea-predominant IBS in women, and it has not been well studied in pregnant people. Animal studies did not show birth defects, but that does not prove safety in humans, so the label leaves the decision to you and your prescriber. The drug also carries a boxed warning about serious constipation and ischemic colitis, and pregnancy already slows digestion on its own. Many people manage IBS diarrhea in pregnancy with fluids, diet changes, and treatments an obstetric clinician signs off on. Raise it at your first prenatal visit instead of deciding alone.
Pregnancy and alosetron: what to know
Common questions
Can you take Alosetron while pregnant?
Alosetron (Lotronex) is approved only for women with severe diarrhea-predominant IBS who have not improved on other treatments, and human pregnancy data are limited, so it is usually stopped during pregnancy. Animal studies have not shown harm, but that alone is not enough to call it safe for you. Alosetron also carries a boxed warning for serious constipation and ischemic colitis, and pregnancy already slows the gut, which is a reason for caution. If you become pregnant while taking it, contact the clinician who prescribed it before your next dose, ask whether to stop, and ask which diarrhea treatments are reasonable while pregnant. Do not restart it on your own after delivery if you plan to breastfeed.