Generic Name: Granisetron Brand Name(s): .


What is Granisetron used for?

Granisetron is commonly used to prevent nausea and vomiting due to cancer drug treatment (chemotherapy) and radiation therapy. It works by blocking one of the body’s chemicals (serotonin) that causes vomiting.

How should I take Granisetron?

Take this medication by mouth. It is important to follow your doctor’s instructions for the timing of each dose. If you have any questions, consult your doctor or pharmacist.

Inform your doctor if your condition persists or worsens.

How do I store Granisetron?

Granisetron is best stored at room temperature away from direct light and moisture. To prevent drug damage, you should not store Granisetron in the bathroom or the freezer. There may be different brands of Granisetron that may have different storage needs. It is important to always check the product package for instructions on storage, or ask your pharmacist. For safety, you should keep all medicines away from children and pets.

You should not flush Granisetron down the toilet or pour them into a drain unless instructed to do so. It is important to properly discard this product when it is expired or no longer needed. Consult your pharmacist for more details about how to safely discard your product.

Precautions & warnings

What should I know before using Granisetron?

Before taking granisetron, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history.

This drug may make you dizzy or drowsy. Do not drive, use machinery, or do any activity that requires alertness until you are sure you can perform such activities safely. Limit alcoholic beverages.

Granisetron may cause a condition that affects the heart rhythm (QT prolongation). QT prolongation can rarely cause serious (rarely fatal) fast/irregular heartbeat and other symptoms (such as severe dizziness, fainting) that need medical attention right away.

The risk of QT prolongation may be increased if you have certain medical conditions or are taking other drugs that may cause QT prolongation. Before using granisetron, tell your doctor or pharmacist of all the drugs you take and if you have any of the following conditions: certain heart problems (heart failure, slow heartbeat, QT prolongation in the EKG), family history of certain heart problems (QT prolongation in the EKG, sudden cardiac death).

Low levels of potassium or magnesium in the blood may also increase your risk of QT prolongation. This risk may increase if you use certain drugs (such as diuretics/”water pills”) or if you have conditions such as severe sweating, diarrhea, or vomiting. Talk to your doctor about using granisetron safely.

Older adults may be more sensitive to the side effects of this drug, especially QT prolongation.

This medication should be used only when clearly needed during pregnancy. Discuss the risks and benefits with your doctor.

It is not known whether this drug passes into breast milk. Consult your doctor before breast-feeding.

Is it safe during pregnancy or breast-feeding?

There are no adequate studies in women for determining risk when using this Granisetron during pregnancy or while breastfeeding. Please always consult with your doctor to weigh the potential benefits and risks before taking Granisetron. Granisetron is pregnancy risk category B according to the US Food and Drug Administration (FDA).

FDA pregnancy risk category reference below:

  • A=No risk,
  • B=No risk in some studies,
  • C=There may be some risk,
  • D=Positive evidence of risk,
  • X=Contraindicated,
  • N=Unknown

Side effects

What side effects can occur from Granisetron?

Diarrhea, constipation, stomach pain, weakness, headache, fever, dizziness, drowsiness, trouble sleeping, and anxiety may occur. If any of these effects persist or worsen, notify your doctor or pharmacist promptly.

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor right away if this highly unlikely but very serious side effect occurs: unusual muscle movements or stiffness.

Seek immediate medical attention if any of these rare but serious side effects occur: chest pain, fast/irregular heartbeat, severe dizziness, fainting.

This medication may increase serotonin and rarely cause a very serious condition called serotonin syndrome/toxicity. The risk increases if you are also taking other drugs that increase serotonin, so tell your doctor or pharmacist of all the drugs you take. Get medical help right away if you develop some of the following symptoms: fast heartbeat, hallucinations, loss of coordination, severe dizziness, severe nausea/vomiting/diarrhea, twitching muscles, unexplained fever, unusual agitation/restlessness.

A serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction include: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

Not everyone experiences these side effects. There may be some side effects not listed above. If you have any concerns about a side-effect, please consult your doctor or pharmacist.


What drugs may interact with Granisetron?

This drug should not be used with the following medication because a very serious interaction may occur: apomorphine.

If you are currently using the medication listed above, tell your doctor or pharmacist before starting granisetron.

Before using this medication, tell your doctor or pharmacist of all prescription and nonprescription products you may use.

Many drugs besides granisetron may affect the heart rhythm (QT prolongation), including amiodarone, dofetilide, pimozide, procainamide, quinidine, sotalol, macrolide antibiotics (such as erythromycin), among others.

The risk of serotonin syndrome/toxicity increases if you are also taking other drugs that increase serotonin. Examples include street drugs such as MDMA/”ecstasy,” St. John’s wort, certain antidepressants (including SSRIs such as fluoxetine/paroxetine, SNRIs such as duloxetine/venlafaxine), among others. The risk of serotonin syndrome/toxicity may be more likely when you start or increase the dose of these drugs.

Keep a list of all your medications with you, and share the list with your doctor and pharmacist.

Granisetron may interact with other drugs that you are currently taking, which can change how your drug works or increase your risk for serious side effects. To avoid any potential drug interactions, you should keep a list of all the drugs you are using (including prescription drugs, nonprescription drugs and herbal products) and share it with your doctor and pharmacist. For your safety, do not start, stop, or change the dosage of any drugs without your doctor’s approval.

Does food or alcohol interact with Granisetron?

Granisetron may interact with food or alcohol by altering the way the drug works or increase the risk for serious side effects. Please discuss with your doctor or pharmacist any potential food or alcohol interactions before using this drug.

What health conditions may interact with Granisetron?

Granisetron may interact with your health condition. This interaction may worsen your health condition or alter the way the drug works. It is important to always let your doctor and pharmacist know all the health conditions you currently have.


The information provided is not a substitute for any medical advice. You should ALWAYS consult with your doctor or pharmacist before using this Granisetron.

What is the dose of Granisetron for an adult?

Usual Adult Dose for Nausea/Vomiting – Chemotherapy Induced

IV: 10 mcg/kg over 5 minutes, beginning 30 minutes before initiation of chemotherapy.

Orally: 2 mg, given up to 1 hour before chemotherapy, or 1 mg twice a day (the first dose is given up to 1 hour before chemotherapy, and the second dose is given 12 hours later).

Granisetron transdermal system: Apply a single patch to the upper outer arm a minimum of 24 hours before chemotherapy. The patch may be applied up to a maximum of 48 hours before chemotherapy as appropriate. Remove the patch a minimum of 24 hours after completion of chemotherapy. The patch can be worn for up to 7 days depending on the duration of the chemotherapy regimen. Granisetron transdermal system is a 52 cm2 patch containing 34.3 mg of granisetron. The patch releases 3.1 mg of granisetron per 24 hours for up to 7 days.

The transdermal system (patch) should be applied to clean, dry, intact healthy skin on the upper outer arm. Granisetron transdermal system should not be placed on skin that is red, irritated or damaged. Each patch is packed in a pouch and should be applied directly after the pouch has been opened. The patch should not be cut into pieces.

Usual Adult Dose for Nausea/Vomiting-Radiation Induced

2 mg orally given within 1 hour of radiotherapy.

Usual Adult Dose for Nausea/Vomiting – Postoperative

Prevention and Treatment

IV: 1 mg undiluted over 30 seconds, given before induction of anesthesia, or immediately before reversal of anesthesia; or give after surgery.

Renal Dose Adjustments

No adjustments recommended

Liver Dose Adjustments

No adjustments recommended

Dose Adjustments

Dosages larger than 40 mcg/kg have not been proven to be significantly superior in the control of nausea and vomiting induced by chemotherapy.

Other Comments

Granisetron should only be given on days that chemotherapy is given. The injectable form can be given undiluted over 30 seconds, or diluted with normal saline or dextrose 5% and infused over 5 minutes (or further diluted to 20 to 50 mL and given over 30 to 60 minutes).

What is the dose of Granisetron for a child?

Usual Pediatric Dose for Nausea/Vomiting – Chemotherapy Induced

Greater than or equal to 2 to 16 years: 10 mcg/kg IV 30 minutes before start of chemotherapy.

Study (n=80)

Randomized double-blind clinical studies have used granisetron injection in the range of 10 to 40 mcg/kg.


Safety and effectiveness of granisetron oral formulations have not been established in pediatric patients (less than 18 years of age). Safety and effectiveness of granisetron IV have not been established in pediatric patients less than 2 years of age due to lack of efficacy and QT prolongation observed in trials.

How is Granisetron available?

Granisetron is available in the following dosage forms and strengths:

  • Oral solution
  • Intravenous solution
  • Oral tablet
  • Transdermal film, extended release,
  • Subcutaneous suspension, extended release

What should I do in case of an emergency or overdose?

In case of an emergency or an overdose, call your local emergency services or go to your nearest emergency room.

What should I do if I miss a dose?

If you miss a dose of Granisetron, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and take your regular dose as scheduled. Do not take a double dose.

Hello Health Group does not provide medical advice, diagnosis or treatment.


Review Date: February 9, 2018 | Last Modified: February 9, 2018

Want to live your best life?
Get the Hello Doktor Daily newsletter for health tips, wellness updates and more.