Uses Of Alosetron

Alosetron is used to treat diarrhea, pain, cramps, and the feeling of an urgent need to have bowel movements caused by irritable bowel syndrome (IBS; a condition that causes stomach pain, bloating, constipation, and diarrhea) in women who have diarrhea as their main symptom and have not been helped by other treatments. Alosetron is in a class of medications called 5-HT3 receptor antagonists. Alosetron works by slowing the movement of stool (bowel movements) through the intestines.

Side Effects Of Alosetron

Alosetron may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • upset stomach
  • swelling in the stomach area
  • hemorrhoids

Some side effects can be serious. If you experience any of the symptoms listed in the IMPORTANT WARNING section, call your doctor immediately.

Warnings & Precautions

Before taking alosetron:

  • tell your doctor and pharmacist if you are allergic to alosetron, any other medications, or any of the ingredients in alosetron tablets. Ask your pharmacist for a list of the ingredients..
  • tell your doctor if you are taking fluvoxamine (Luvox) or the medications listed in the IMPORTANT WARNING section, Your doctor will probably tell you not to take alosetron if you are taking one or more of these medications.
  • tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention any of the following: certain antifungals such as fluconazole (Diflucan), itraconazole (Sporanox), ketoconazole (Nizoral), and voriconazole (Vfend); cimetidine (Tagamet); clarithromycin (Biaxin, in Prevpac); fluoroquinolone antibiotics including ciprofloxacin (Cipro), gatifloxacin (Tequin), levofloxacin (Levaquin), norfloxacin (Noroxin), ofloxacin (Floxin), others; hydralazine (apresoline); isoniazid (INH, Nydrazid); certain medications for human immunodeficiency virus (HIV) or acquired immunodeficiency syndrome (AIDS) such as atazanavir (Reyataz), darunavir (Prezista), fosamprenavir (Lexiva), indinavir (Crixivan), lopinavir (in Kaletra), nelfinavir (Viracept), ritonavir (Norvir, in Kaletra), saquinavir (Fortovase, Invirase), and tipranavir (Aptivus); procainamide (Procanbid, Pronestyl); and telithromycin (Ketek). Many other medications may also interact with alosetron, so be sure to tell your doctor about all the medications you are taking, even those that do not appear on this list. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
  • tell your doctor if you have or have ever had the conditions listed in the IMPORTANT WARNING section or any stomach or bowel problems, surgery to your stomach or bowels, or kidney disease.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking alosetron, call your doctor.


Alosetron comes as a tablet to take by mouth. It is usually taken twice a day with or without food. Take alosetron at around the same times every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take alosetron exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Your doctor will probably start you on a low dose of alosetron. Your doctor will want to talk to you after you have taken the low dose for 4 weeks. If your symptoms are not controlled but you are not experiencing serious side effects of alosetron, your doctor may increase your dose. If you take the increased dose for 4 weeks and your symptoms are still not controlled, alosetron is not likely to help you. Stop taking alosetron and call your doctor.
Alosetron may control IBS but will not cure it. If alosetron helps you and you stop taking it, your IBS symptoms may return within 1 or 2 weeks.


Keep all appointments with your doctor.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.


All information has been provided courtesy of MedLinePlus from the National Library of Medicine and from the FDA.