Medication Information Leaflet

What is this medication for?

Entecavir is used to treat chronic hepatitis B virus infection.

How should I take/use this medication?

  • You may take this medication one hour before or two hours after food.

  • This medication does not cure hepatitis B, if stopped inappropriately your condition may worsen. Do not stop taking your medication without checking with your healthcare professional.

  • If your symptoms worsen despite treatment with this medication, consult your healthcare professional.

What should I do if I forget to take/use this medication?

If you forget to take a dose, take it as soon as you remember. Then take your next dose at the usual time. Do not take two doses to make up for the missed dose.

What precautions should I take?

Inform your healthcare professional if:

  • You are allergic to this medication or any of the other ingredients of this medication.

  • You are pregnant, planning to become pregnant, or breastfeeding.

  • You are taking any other medications, including supplements, traditional medications and herbal remedies.

  • This medication does not prevent the spread of hepatitis whether through unprotected sexual intercourse or through the sharing of needles.

  • You may be required to have your blood checked at intervals while taking this medication to monitor for its effectiveness and safety.

What are some common side-effects of this medication?

  • Gastrointestinal side effects,such as dyspepsia, diarrhoea, nausea and vomiting.

  • Some people experience fatigue, headaches, dizziness, and drowsiness.

What are some rare but serious side-effects that I need to seek medical advice immediately?

The symptoms of a drug allergy include one or more of the following:

  • Swollen face/eyes/lips/tongue

  • Difficulty in breathing

  • Itchy skin rashes over your whole body

If you experience any of these symptoms, you should stop your medication and see your healthcare professional immediately.

In rare cases side effects such as a deterioration in liver function and/or an enlarged liver may occur. Some may experience an increased acidity in the blood. If you experience any of the following consult your healthcare professional immediately.

  • Worsening liver problems. This may include symptoms such as darkened urine, fatigue, persistent gastrointestinal pain or discomfort, light coloured stools, persistent nausea and vomiting, and/or yellowing of the skin or eyes.

  • Signs of excessive acid in the blood may include an altered heartbeat, gastrointestinal tract discomfort, persistent sleepiness, shortness of breath, tiredness, dizziness, and muscle pain or cramps.

What food or medication should I avoid when I take this medication?

Entecavir can generally be taken with most other foods or medications. However, please inform your healthcare professionals if you are taking other medications or herbal preparations.

How should I store this medication?

Store in a cool and dry place, away from direct sunlight. Keep this medication away from children.

How should I throw away this medication safely?

Pack this medication into a black trash bag and seal it tightly before throwing it into the rubbish chute or bin.


If you take more than the recommended dose, please seek medical advice immediately. The information provided on this page does not replace information from your healthcare professional. Please consult your healthcare professional for more information.

This article is jointly developed by members of the National Medication Information workgroup. The workgroup consists of cluster partners (National Healthcare Group, National University Health System and SingHealth), community pharmacies (Guardian, Unity and Watsons) and Pharmaceutical Society of Singapore. The content does not reflect drug availability and supply information in pharmacies and healthcare institutions. You are advised to check with the respective institutions for such information.

Last updated: Jun 2022

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