Granisetron blocks the actions of chemicals in the body that can trigger nausea and vomiting.

Granisetron is used to prevent nausea and vomiting that may be caused by medicine to treat cancer (chemotherapy or radiation).

Granisetron may be used for other purposes not listed in this medication guide.

You should not use this medication if you are allergic to granisetron or to similar medicines such as dolasetron (Anzemet), ondansetron (Zofran), or palonosetron (Aloxi).

Before taking granisetron, tell your doctor if you have liver disease, a heart rhythm disorder, an electrolyte imbalance (such as low levels of potassium or magnesium in your blood), or a personal or family history of Long QT syndrome.

Granisetron is usually started up to 1 hour before chemotherapy. Tell your doctor if you forget to take the medication within the specified amount of time before your procedure.

You should not use this medication if you are allergic to granisetron, to similar medicines such as dolasetron (Anzemet), ondansetron (Zofran), or palonosetron (Aloxi).

If you have any of these other conditions, you may need a dose adjustment or special tests to safely take granisetron:

• liver disease;

• a heart rhythm disorder;

• an electrolyte imbalance (such as low levels of potassium or magnesium in your blood); or

• a personal or family history of Long QT syndrome.

FDA pregnancy category B. This medication is not expected to be harmful to an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant during treatment.

It is not known whether granisetron passes into breast milk or if it could harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby.