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URL of this page: https://medlineplus.gov/druginfo/meds/a601211.html

Granisetron

pronounced as (gra ni' se tron)

Why is this medication prescribed?

Why is this medication prescribed? has been expanded.

Granisetron is used to prevent nausea and vomiting caused by cancer chemotherapy and radiation therapy. Granisetron is in a class of medications called 5-HT3 receptor antagonists. It works by blocking serotonin, a natural substance in the body that causes nausea and vomiting.

How should this medicine be used?

Granisetron comes as a tablet to take by mouth. When taken to prevent nausea and vomiting caused by chemotherapy, granisetron is usually taken 1 hour before chemotherapy is begun. A second dose may be taken 12 hours after the first dose depending on the strength. When taken to prevent nausea and vomiting caused by radiation, granisetron is usually taken within 1 hour before treatment. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take granisetron exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Other uses for this medicine

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

What special precautions should I follow?

Before taking granisetron,

  • tell your doctor and pharmacist if you are allergic to granisetron, alosetron (Lotronex), dolasetron (Anzemet), ondansetron (Zofran, Zuplenz), palonosetron (Aloxi, in Akynzeo), any other medications, or any of the ingredients in granisetron tablets. Ask your pharmacist for a list of the ingredients.
  • tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take while taking granisetron. Your doctor may need to change the doses of your medications or monitor you carefully for side effects. .
  • tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. If you become pregnant while taking granisetron, call your doctor.

What special dietary instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What should I do if I forget a dose?

Granisetron should only be taken before chemotherapy or radiation therapy, as instructed by your doctor. It should not be taken on a regularly scheduled basis.

What side effects can this medication cause?

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

  • headache
  • stomach pain
  • heartburn
  • constipation
  • difficulty falling asleep or staying asleep

Some side effects can be serious. If you experience any of the following symptoms, call your doctor immediately or seek emergency medical treatment:

  • hives
  • rash
  • itching
  • difficulty breathing or swallowing
  • shortness of breath
  • dizziness, light-headedness, or fainting
  • fast, slow or irregular heartbeat
  • agitation
  • hallucinations (seeing things or hearing voices that do not exist)
  • fever
  • flushing
  • excessive sweating
  • confusion
  • nausea, vomiting, or diarrhea
  • loss of coordination
  • stiff or twitching muscles
  • seizures
  • coma (loss of consciousness)

Granisetron may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (https://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

What should I know about storage and disposal of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

Dispose of unneeded medications in a way so that pets, children, and other people cannot take them. Do not flush this medication down the toilet. Use a medicine take-back program. Talk to your pharmacist about take-back programs in your community. Visit the FDA's Safe Disposal of Medicines website https://goo.gl/c4Rm4p for more information.

Keep all medication out of sight and reach of children as many containers are not child-resistant. Always lock safety caps. Place the medication in a safe location – one that is up and away and out of their sight and reach. https://www.upandaway.org

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

Symptoms of overdose may include the following:

  • headache

What other information should I know?

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.

Keep a written list of all of the prescription and nonprescription (over-the-counter) medicines, vitamins, minerals, and dietary supplements you are taking. Bring this list with you each time you visit a doctor or if you are admitted to the hospital. You should carry the list with you in case of emergencies.

Brand names

  • Kytril®

This branded product is no longer on the market. Generic alternatives may be available.

Last Revised - 07/20/2024