SIDE EFFECTS: Headache, fatigue, dizziness, and nausea may occur. If any of these effects persist or worsen, notify your doctor or pharmacist 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.

A very serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction may 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.

Read the Baraclude (entecavir) Side Effects Center for a complete guide to possible side effects »

PRECAUTIONS: Before taking entecavir, tell your doctor or pharmacist if you are allergic to it; 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: HIV infection, kidney disease.

Kidney function declines as you grow older. This medication is removed by the kidneys. Therefore, elderly people may be more sensitive to this drug, and to side effects such as lactic acidosis.

This medication should be used only when clearly needed during pregnancy. Discuss the risks and benefits with your doctor.

It is unknown if this drug passes into breast milk. Breast-feeding is not recommended while using this drug if you also have HIV. Otherwise, consult your doctor before breast-feeding.