ondansetron - oral, Zofran (cont.)
SIDE EFFECTS: Headache, lightheadedness, dizziness, drowsiness, tiredness, or constipation may occur. If these effects persist or worsen, notify your doctor 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 immediately if any of these unlikely but serious side effects occur: stomach pain, muscle spasm/stiffness, vision changes (e.g., temporary loss of vision, blurred vision).Get medical help right away if any of these rare but very serious side effects occur: chest pain, slow/fast/irregular heartbeat, severe dizziness, fainting.A very serious allergic reaction to this drug is unlikely, but stop taking this medication and 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.This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.In the US -Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
PRECAUTIONS: Before taking ondansetron, tell your doctor or pharmacist if you are allergic to it; or to other serotonin blockers (e.g., granisetron); 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, especially of: irregular heartbeat, liver disease, stomach/intestinal problems (e.g., recent abdominal surgery, ileus, swelling).Ondansetron may cause a condition that affects the heart rhythm (QT prolongation). QT prolongation can infrequently result in 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 ondansetron, 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 ondansetron safely.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.To minimize dizziness and lightheadedness, get up slowly when rising from a sitting or lying position.Older adults may be more sensitive to the side effects of this drug, especially QT prolongation (see above).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.
Medically Reviewed by a Doctor on 4/16/2014
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