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Generic name: tenofovir alafenamide
Drug class: Nucleoside reverse transcriptase inhibitors (NRTIs)

Medically reviewed by Philip Thornton, DipPharm. Last updated on Nov 3, 2021.

What is Vemlidy?

Vemlidy is a prescription antiviral medicine that prevents the hepatitis B virus from multiplying in your body.

Vemlidy is used to treat patients with chronic hepatitis B infection in adults with compensated liver disease.

Vemlidy may lower the amount of HBV in your body and may improve the condition of your liver.

It is not known if Vemlidy is safe and effective in children under 18 years of age.


If you have hepatitis B, it may become active or get worse after you stop using Vemlidy. You may need frequent liver function tests for several months.

Do not stop using Vemlidy without first talking to your doctor. If you have ever had hepatitis B, stopping treatment with tenofovir can cause acute exacerbations of hepatitis B. You will need frequent blood tests to check your liver function.

Vemlidy is not recommended in patients with end stage renal disease.

Tenofovir alafenamide (Vemlidy) is used to treat patients with chronic hepatitis B. Tenofovir disoproxil (Viread) is used to treat HIV-1 infection and chronic hepatitis B.

Before taking this medicine

You should not take Vemlidy if you are allergic to tenofovir.

Do not take Vemlidy together with adefovir (Hepsera), or with combination medicines that contain tenofovir (Atripla, Biktarvy, Cimduo, Complera, Descovy, Genvoya, Odefsey, Stribild, Symfi, or Truvada).

To make sure Vemlidy is safe for you, tell your doctor if you have ever had:

  • liver disease (especially hepatitis B if you also have HIV);

  • HIV (if you are taking tenofovir to treat hepatitis B);

  • kidney disease; or

  • low bone mineral density.

You may develop lactic acidosis, a dangerous build-up of lactic acid in your blood. Ask your doctor about your risk.

Tell your doctor if you are pregnant, and use your medications properly to control your infection.

It may not be safe to breastfeed while using Vemlidy. Ask your doctor about any risk.

How should I take Vemlidy?

Take Vemlidy exactly as prescribed by your doctor. Follow all directions on your prescription label and read all medication guides or instruction sheets.

Before you start treatment with Vemlidy, your doctor may perform tests to make sure you do not have HIV (if you are being treated for hepatitis B).

Take this medicine once daily at the same time each day. Take Vemlidy with food.

Do not miss a dose of Vemlidy.

Do not change your dose or stop taking Vemlidy without first talking with your healthcare provider. Stay under a healthcare provider's care when taking this medicine.

If you are on dialysis, on your dialysis days, take your daily dose of Vemlidy following dialysis.

If you've had hepatitis B, it may come back or get worse after you stop using Vemlidy. You may need liver function tests while using this medicine and for several months after you stop.

Store tightly closed at room temperature, away from moisture and heat.

Dosing information

Usual Adult Dose for Chronic Hepatitis B:

Tenofovir alafenamide: 25 mg orally once a day

Uses: For the treatment of chronic HBV infection in patients with compensated liver disease.

What happens if I miss a dose?

Take the medicine as soon as you can, but skip the missed dose if it is almost time

When your Vemlidy supply starts to run low, get more from your healthcare provider or pharmacy. This is very important because your HBV infection may get worse (flare-up) if you stop taking this medicine.

What happens if I overdose?

If you take too much Vemlidy, call your healthcare provider or go to the nearest hospital emergency room right away.

What should I avoid while taking Vemlidy?

Drinking alcohol may increase your risk of liver damage.

Taking Vemlidy will not prevent you from passing hepatitis B to other people.

Vemlidy side effects

Get emergency medical help if you have signs of an allergic reaction to Vemlidy: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Mild symptoms of lactic acidosis may worsen over time, and this condition can be fatal. Get emergency medical help if you have: unusual muscle pain, trouble breathing, stomach pain, vomiting, fast/slow or irregular heartbeats, dizziness, feeling cold, or feeling very weak or tired.

Call your doctor at once if you have:

  • sore throat, flu symptoms, easy bruising or unusual bleeding;

  • kidney problems - little or no urination, painful or difficult urination, swelling in your feet or ankles, feeling tired or short of breath; or

  • liver problems - swelling around your midsection, upper stomach pain, unusual tiredness, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes).

Tenofovir can affect your immune system (even weeks or months after you've used this medicine). Tell your doctor if you have:

  • signs of a new infection - fever, night sweats, swollen glands, cold sores, cough, wheezing, diarrhea, weight loss;

  • trouble speaking or swallowing, problems with balance or eye movement, weakness or prickly feeling; or

  • swelling in your neck or throat (enlarged thyroid), menstrual changes, impotence.

Common Vemlidy side effects may include:

  • stomach pain, nausea, vomiting, diarrhea;

  • fever, pain;

  • weakness, dizziness;

  • headache;

  • depressed mood;

  • itching, rash; or

  • sleep problems (insomnia).

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect Vemlidy?

Sometimes it is not safe to use certain medications at the same time. Some drugs can affect your blood levels of other drugs you take, which may increase side effects or make the medications less effective.

Tenofovir can harm your kidneys, especially if you also use certain medicines for infections, cancer, osteoporosis, organ transplant rejection, high blood pressure, or pain or arthritis (including Advil, Motrin, and Aleve).

Many drugs can interact with tenofovir. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed here. Tell your doctor about all other medicines you use.

Popular FAQ

Vemlidy (tenofovir alafenamide) and Viread (Tenofovir disproxil fumarate) are antiviral medications marketed by Gilead Sciences. They are both prodrugs of tenofovir.
Vemlidy and Viread are similar in terms of their effectiveness, but Vemlidy is effective at a much lower dose than Viread. Less tenofovir ends up in the bloodstream after taking Vemlidy, leading to improved renal and bone laboratory safety parameters compared with Viread.

Vemlidy also has greater plasma stability, enabling it to deliver tenofovir to hepatocytes more efficiently.

Vemlidy and Viread are both used to treat chronic hepatitis B virus (HBV) infection, but Viread is also used in the treatment of human immunodeficiency virus-1 (HIV-1) infection.

  Continue reading

Biktarvy (bictegravir, emtricitabine and tenofovir alafenamide) can increase cholesterol levels due to the tenofovir alafenamide (TAF) component, but this does not appear to be a frequent or significant side effect. Continue reading

More FAQ

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use Vemlidy only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.