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Generic name: Granisetron Extended-Release Injectiongra-NI-se-tron ]
Drug class: 5HT3 receptor antagonists

Medically reviewed by Last updated on Feb 5, 2023.

Uses of Sustol:

What do I need to tell my doctor BEFORE I take Sustol?

  • If you have an allergy to granisetron or any other part of Sustol (granisetron extended-release injection).
  • If you are allergic to Sustol (granisetron extended-release injection); any part of Sustol (granisetron extended-release injection); or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
  • If you have kidney problems.

This is not a list of all drugs or health problems that interact with Sustol (granisetron extended-release injection).

Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take Sustol (granisetron extended-release injection) with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

What are some things I need to know or do while I take Sustol?

  • Tell all of your health care providers that you take Sustol (granisetron extended-release injection). This includes your doctors, nurses, pharmacists, and dentists.
  • Tell your doctor if you are pregnant, plan on getting pregnant, or are breast-feeding. You will need to talk about the benefits and risks to you and the baby.
  • It is common to have injection site reactions with Sustol (granisetron extended-release injection). Some injection site reactions may happen up to 2 weeks or more after getting Sustol (granisetron extended-release injection). Some of these reactions may be very bad and need treatment. Talk with your doctor.
  • Allergic reactions may happen up to 7 days or more after getting Sustol (granisetron extended-release injection). Talk with your doctor.

How is this medicine (Sustol) best taken?

Use Sustol (granisetron extended-release injection) as ordered by your doctor. Read all information given to you. Follow all instructions closely.

  • It is given as a shot into the fatty part of the skin.

What do I do if I miss a dose?

  • Call your doctor to find out what to do.

What are some side effects that I need to call my doctor about right away?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

  • Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
  • Chest pain or pressure.
  • Fast or abnormal heartbeat.
  • Very bad dizziness or passing out.
  • Shortness of breath.
  • Fever, chills, or sore throat.
  • Stomach pain.
  • Swelling of belly.
  • A severe and sometimes deadly problem called serotonin syndrome may happen. The risk may be greater if you also take certain other drugs. Call your doctor right away if you have agitation; change in balance; confusion; hallucinations; fever; fast or abnormal heartbeat; flushing; muscle twitching or stiffness; seizures; shivering or shaking; sweating a lot; severe diarrhea, upset stomach, or throwing up; or very bad headache.
  • Injection site pain or tenderness that you need to take a pain drug for or that causes problems with daily living.
  • Area that feels hard or bruise at the injection site that does not go away.
  • Signs of infection at the injection site like redness, warmth of the skin, or fever.
  • Bleeding at the injection site that is very bad or lasts longer than 24 hours.
  • Constipation that may be very bad can happen with Sustol (granisetron extended-release injection). This can happen up to 7 days after getting Sustol (granisetron extended-release injection). Some people have had to go to the hospital to be treated for very bad constipation. Call your doctor right away if you have constipation or if it gets worse after you use Sustol (granisetron extended-release injection).

What are some other side effects of Sustol?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

  • Headache.
  • Feeling dizzy, tired, or weak.
  • Diarrhea or constipation.
  • Heartburn.
  • Trouble sleeping.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at

If OVERDOSE is suspected:

If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

How do I store and/or throw out Sustol?

  • If you need to store Sustol (granisetron extended-release injection) at home, talk with your doctor, nurse, or pharmacist about how to store it.

Consumer Information Use and Disclaimer

  • If your symptoms or health problems do not get better or if they become worse, call your doctor.
  • Do not share your drugs with others and do not take anyone else's drugs.
  • Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
  • Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.
  • This medicine comes with an extra patient fact sheet called a Medication Guide. Read it with care. Read it again each time Sustol (granisetron extended-release injection) is refilled. If you have any questions about Sustol (granisetron extended-release injection), please talk with the doctor, pharmacist, or other health care provider.
  • If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

Frequently asked questions

Further information

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