ondansetron (oral)

What is the most important information I should know about ondansetron?

What is ondansetron?

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

Ondansetron is used to prevent nausea and vomiting that may be caused by surgery, cancer chemotherapy, or radiation treatment.

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

What should I discuss with my health care provider before taking ondansetron?

• you are also using apomorphine (Apokyn); or
• you are allergic to ondansetron or similar medicines (dolasetron, granisetron, palonosetron).

To make sure ondansetron is safe for you, tell your doctor if you have:

• liver disease;
• an electrolyte imbalance (such as low levels of potassium or magnesium in your blood);
• congestive heart failure, slow heartbeats;
• a personal or family history of long QT syndrome; or
• a blockage in your digestive tract (stomach or intestines).

Ondansetron is not expected to harm an unborn baby. Tell your doctor if you are pregnant.

Ondansetron orally disintegrating tablets may contain phenylalanine. Tell your doctor if you have phenylketonuria (PKU).

How should I take ondansetron?

Follow all directions on your prescription label. Do not take this medicine in larger or smaller amounts or for longer than recommended.

Ondansetron can be taken with or without food.

The first dose of ondansetron is usually taken before the start of your surgery, chemotherapy, or radiation treatment. Follow your doctor's dosing instructions very carefully.

To take the orally disintegrating tablet (Zofran ODT):

• Keep the tablet in its blister pack until you are ready to take it. Open the package and peel back the foil. Do not push a tablet through the foil or you may damage the tablet.
• Use dry hands to remove the tablet and place it in your mouth.
• Do not swallow the tablet whole. Allow it to dissolve in your mouth without chewing.
• Swallow several times as the tablet dissolves.

To use ondansetron oral soluble film (strip) (Zuplenz):

• Keep the strip in the foil pouch until you are ready to use the medicine.
• Using dry hands, remove the strip and place it on your tongue. It will begin to dissolve right away.
• Do not swallow the strip whole. Allow it to dissolve in your mouth without chewing.
• Swallow several times after the strip dissolves. If desired, you may drink liquid to help swallow the dissolved strip.
• Wash your hands after using Zuplenz.

Measure liquid medicine with the dosing syringe provided, or with a special dose-measuring spoon or medicine cup. If you do not have a dose-measuring device, ask your pharmacist for one.

What happens if I miss a dose?

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Overdose symptoms may include sudden loss of vision, severe constipation, feeling light-headed, or fainting.

What should I avoid while taking ondansetron?

What are the possible side effects of ondansetron?

• severe constipation, stomach pain, or bloating;
• headache with chest pain and severe dizziness, fainting, fast or pounding heartbeats;
• fast or pounding heartbeats;
• jaundice (yellowing of the skin or eyes);
• blurred vision or temporary vision loss (lasting from only a few minutes to several hours);
• high levels of serotonin in the body --agitation, hallucinations, fever, fast heart rate, overactive reflexes, nausea, vomiting, diarrhea, loss of coordination, fainting.

Common side effects may include:

• diarrhea or constipation;
• headache;
• drowsiness; or
• tired feeling.

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.

What other drugs will affect ondansetron?

Ondansetron can cause a serious heart problem, especially if you use certain medicines at the same time, including antibiotics, antidepressants, heart rhythm medicine, antipsychotic medicines, and medicines to treat cancer, malaria, HIV or AIDS. Tell your doctor about all medicines you use, and those you start or stop using during your treatment with ondansetron.

• medicine to treat depression;
• medicine to treat a psychiatric disorder;
• a narcotic (opioid) medication; or
• medicine to prevent nausea and vomiting.

This list is not complete and many other drugs can interact with ondansetron. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Give a list of all your medicines to any healthcare provider who treats you.

Where can I get more information?

Your pharmacist can provide more information about ondansetron.