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Patient information A-Z

Who is the leaflet for?

This leaflet is for patients starting on treatment with tenofovir for hepatitis B infection to provide an overview of treatment and important information.

About tenofovir

What is tenofovir and how do I take it?

Tenofovir is an antiviral medication commonly used to treat long-term hepatitis B virus infection, which can cause inflammation and damage to the liver. Tenofovir reduces the amount of hepatitis B virus in your body to limit damage to your liver. It is a tablet which should be taken by mouth. It is usually given at a dose of 245mg once a day with food (for example a meal or a snack). Your doctor or liver nurse specialist may prescribe a different dose if there are problems with your kidney function.

Tenofovir is usually continued long-term. Do not stop taking tenofovir without discussion with your doctor or liver nurse specialist. Your hepatitis B virus infection may get worse if you stop taking tenofovir.

Are there any problems with taking tenofovir?

Broadly, tenofovir is safe and well tolerated but you should be aware of the following issues.

Side effects

The most common side effects from tenofovir include headache, tiredness, dizziness, weakness, nausea, vomiting, diarrhoea, abdominal pain, bloating, flatulence and rashes.

Increased blood levels of liver enzymes: contact your doctor or liver nurse specialist if you experience new signs or symptoms of liver problems, for example skin or white part of your eye turning yellow, dark urine, nausea, abdominal pain, lack of appetite.

Lactic acidosis (build-up of acid in the blood): a rare but serious side effect that must be treated in hospital. Contact your doctor or liver nurse specialist immediately if you experience severe abdominal pain with nausea and vomiting.

If you experience any side effects, please contact your doctor, pharmacist or liver nurse specialist. This includes any possible side effects not listed above.

Blood tests will need to be taken regularly whilst taking tenofovir to monitor your liver and kidney function; your liver nurse specialist will discuss this with you. Should you become very unwell soon after starting the medication, please contact your doctor or liver nurse specialist.

Missed doses

To prevent viral mutation and liver damage, it is very important that you do not miss doses of tenofovir. If you do miss a dose but remember within twelve hours since you should have taken your dose then take your usual dose. If it has been more than twelve hours then skip the missed dose, but take your next dose when it is due. Do not take a double dose to make up for a missed dose.

If you are sick within one hour after taking your tenofovir dose you should take an additional tablet. If you are sick again, you do not need to take a third tablet.


If you are pregnant, think you may be pregnant or you wish to plan a pregnancy on tenofovir, this should be discussed carefully with your doctor first.

If you or your partner are of childbearing age, it is important that you take precautions to prevent pregnancy with effective contraception whilst you are on treatment and for at least six weeks after you stop treatment.


It is safe to continue taking tenofovir whilst breastfeeding. You should notify your doctor or liver nurse specialist if this is the case.

Additional information

Only take medicines prescribed for you by your doctor and check with your doctor, liver nurse specialist or pharmacist before taking any new medicines. This includes medicines initiated by your GP or medicines/ remedies bought over the counter.

Before commencing tenofovir, it is important that you tell your doctor or pharmacist if you are taking medication for hepatitis C or HIV. This is because there may be interactions which may change how well these medications work, or may lead to a change in treatment.

Can I spread hepatitis B whilst I am on treatment?

Treatment with tenofovir for hepatitis B does not stop you from passing the infection on, for example through sexual contact or bodily fluids including blood, so make sure that you continue to take appropriate preventative measures. These can be discussed in more detail with your doctor or liver nurse specialist.

Further information

Further information about your tablet can be found in the patient information leaflet found in the tablet/ capsule box or on the container.

Further information on hepatitis B can be found on the following websites:

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Other formats

Help accessing this information in other formats is available. To find out more about the services we provide, please visit our patient information help page (see link below) or telephone 01223 256998.

Contact us

Cambridge University Hospitals
NHS Foundation Trust
Hills Road, Cambridge

Telephone +44 (0)1223 245151