Ondansetron Side Effects and Warnings

What are the precautions when taking this medicine?

• If you have a heart condition called congenital QT syndrome, talk with healthcare provider.

• If you have liver disease, talk with healthcare provider.

• If you have low potassium or magnesium levels, talk with healthcare provider.

• Check medicines with healthcare provider. This medicine may not mix well with other medicines.

• If you have PKU, talk with healthcare provider. Some products do contain phenylalanine.

• You may not be alert. Avoid driving, doing other tasks or activities until you see how this medicine affects you.

• Tell healthcare provider if you are pregnant or plan on getting pregnant.

• Tell healthcare provider if you are breast-feeding.

What are some possible side effects of this medicine?

• Headache.

• Feeling tired or weak.

• Constipation. More liquids, regular exercise, or a fiber-containing diet may help. Talk with healthcare provider about a stool softener or laxative.

• Feeling dizzy. Rise slowly over several minutes from sitting or lying position. Be careful climbing.

• Feeling lightheaded, sleepy, having blurred vision, or a change in thinking clearly. Avoid driving, doing other tasks or activities that require you to be alert or have clear vision until you see how this medicine affects you.

• A faster, harmful heartbeat can rarely occur.

Reasons to call healthcare provider immediately

• If you suspect an overdose, call your local poison control center or emergency department immediately.

• Signs of a life-threatening reaction. These include wheezing; chest tightness; fever; itching; bad cough; blue skin color; fits; or swelling of face, lips, tongue, or throat.

• Fast heartbeat.

• Significant change in thinking clearly and logically.

• Severe headache.

• Feeling extremely tired or weak.

• Any rash.

• No improvement in condition or feeling worse.