Alosetron

Generic name: alosetron [ a-LO-ze-tron ]
Brand name: Lotronex
Dosage form: oral tablet (0.5 mg; 1 mg)
Drug class: Serotoninergic neuroenteric modulators

Medically reviewed by Drugs.com on Mar 25, 2024. Written by Cerner Multum.

What is alosetron?

Alosetron is used to treat severe chronic irritable bowel syndrome (IBS) in women who have diarrhea as their main symptom. Alosetron is given after other treatments did not work or stopped working.

Alosetron is not a cure for irritable bowel syndrome. Alosetron may not provide relief in every person who takes it. alosetron can help reduce stomach pain and discomfort, the sudden need to have a bowel movement, and diarrhea.

This medicine is not approved for use by men or anyone younger than 18 years old with irritable bowel syndrome.

Alosetron may also be used for purposes not listed in this medication guide.

Alosetron side effects

Get emergency medical help if you have signs of an allergic reaction: hives, difficult breathing, swelling of your face, lips, tongue, or throat.

Some people have had serious or fatal side effects that may lead to a hospital stay, blood transfusions or surgery while taking alosetron. Stop taking alosetron and call your doctor at once if you have:

• new or worsening constipation; or

• signs of circulation problems affecting your intestines--new or worsening stomach pain, blood in your stools, or bloody diarrhea.

Your treatment may be permanently discontinued if you have certain side effects.

Serious side effects may be more likely in older adults and those who are ill or debilitated.

Common side effects of alosetron may include:

• constipation;

• nausea; or

• stomach or intestinal pain and discomfort.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Related/similar drugs

Warnings

You should not start taking alosetron if you are constipated.

Alosetron should be used only by women with severe chronic irritable bowel syndrome and who have diarrhea as the main symptom.

Tell your doctor about all your other medicines. Some drugs should not be used with alosetron.

Some people have had serious or fatal side effects while taking alosetron. Stop taking alosetron and call your doctor right away if you have: new or worsening constipation, stomach pain, blood in your stools, or bloody diarrhea.

If you stop using alosetron, do not start it again without your doctor's advice.

Before taking this medicine

You should not use alosetron if you have:

• constipation (caused by disease or by using certain medicines);

• bowel obstruction, a perforation (a hole or tear) of your intestines, colitis or toxic megacolon;

• a history of severe or ongoing constipation;

• Crohn's disease, ulcerative colitis, diverticulitis;

• blood clots, or circulation problems affecting your intestines; or

• severe liver disease.

Some drugs should not be used with alosetron. Your treatment plan may change if you also use fluvoxamine.

Tell your doctor if you have ever had:

• a history of inflammatory bowel disease;

• any allergies or other condition; or

• liver disease.

Tell your doctor if you are pregnant or breastfeeding.

If you are breastfeeding, tell your doctor if you notice constipation or bloody stools in the nursing baby.

How should I take alosetron?

You should not start taking alosetron if you are constipated.

Follow all directions on your prescription label and read all medication guides or instruction sheets. Your doctor may occasionally change your dose. Use the medicine exactly as directed.

Alosetron is taken twice a day. You may take alosetron with or without food. Follow your doctor's dosing instructions very carefully.

Call your doctor if your symptoms do not improve after 4 weeks, or if they get worse. Stop taking alosetron if you start having constipation at any time. Call your doctor again if the constipation does not improve.

Your condition may get worse in 1 or 2 weeks if you stop using alosetron suddenly. If you stop using alosetron, do not start it again without your doctor's advice.

Your doctor will need to check your progress about every 4 weeks.

Store at room temperature away from moisture, heat, and light.

Alosetron dosing information

Usual Adult Dose for Irritable Bowel Syndrome:

Initial dose: 0.5 mg orally twice a day
Maintenance dose: 0.5 mg orally once or twice a day; may be increased up to 1 mg orally twice a day after 4 weeks of treatment.
Maximum dose: 2 mg/day

Comment: Due to the serious gastrointestinal adverse reactions associated with this drug, treatment should be restricted to female patients for whom the benefit-to-risk balance is most favorable.

Use: Women with severe diarrhea-predominant irritable bowel syndrome (IBS) who have chronic IBS symptoms (generally lasting 6 months or longer), had anatomic or biochemical abnormalities of the gastrointestinal tract excluded, and have not responded adequately to conventional therapy

What happens if I miss a dose?

Skip the missed dose and use your next dose at the regular time. Do not use two doses at one time.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking alosetron?

Follow your doctor's instructions about any restrictions on food, beverages, or activity.

What other drugs will affect alosetron?

Sometimes it is not safe to use certain medicines at the same time. Some drugs can affect your blood levels of other drugs you use, which may increase side effects or make the medicines less effective.

Many drugs can affect alosetron. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed here. Tell your doctor about all other medicines you use.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Medical Disclaimer

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