An Overview of Viread (Tenofovir)

Brand Name: Viread
Other Names: TDF, tenofovir DF
Drug Class: Nucleoside Reverse Transcriptase Inhibitors

Viread 200mg tablet


Tenofovir disoproxil fumarate (tenofovir DF) can cause serious, life-threatening side effects. These include a buildup of lactic acid in the blood (lactic acidosis) and severe liver problems.

Contact your health care provider right away if you have any of the following symptoms that could be signs of lactic acidosis:

  • Feeling very weak or tired
  • Unusual muscle pain
  • Trouble breathing
  • Stomach pain with nausea or vomiting
  • Feeling cold, especially in your arms and legs
  • Feeling dizzy or lightheaded
  • Fast or irregular heartbeat

Contact your health care provider right away if you have any of the following symptoms that could be signs of severe liver problems:

  • Yellowing of your skin or the whites of your eyes (jaundice)
  • Dark-colored urine
  • Light-colored bowel movements
  • Loss of appetite for several days or longer
  • Nausea
  • Stomach pain

If you have both HIV and hepatitis B virus (HBV) infection and take tenofovir DF, your HBV infection may get much worse (flare up) if you stop taking tenofovir DF. The HBV drug adefovir dipivoxil (brand name: Hepsera) should not be taken with tenofovir DF.

While taking tenofovir DF, it is important to keep all of your appointments with your health care provider.

What Is Tenofovir Disoproxil Fumarate?

Tenofovir DF is a prescription medicine approved by the U.S. Food and Drug Administration (FDA) for the treatment of HIV infection in adults and children 2 years of age and older. Tenofovir DF is always used in combination with other HIV medicines.

Tenofovir DF belongs to a class (group) of HIV drugs called nucleoside reverse transcriptase inhibitors (NRTIs). NRTIs block an HIV enzyme called reverse transcriptase. (An enzyme is a protein that starts or increases the speed of a chemical reaction.) By blocking reverse transcriptase, NRTIs prevent HIV from multiplying and can reduce the amount of HIV in the body.

HIV medicines can't cure HIV/AIDS, but taking a combination of HIV medicines (called an HIV regimen) every day helps people with HIV live longer, healthier lives. HIV medicines also reduce the risk of HIV transmission. If you are taking HIV medicines, including tenofovir DF, don't cut down on, skip, or stop taking them unless your health care provider tells you to.

Tenofovir DF is also effective against HBV and approved by FDA for the treatment of chronic HBV infection in adults and children 12 years of age and older. For information on the HBV-related use of tenofovir DF in people with HIV, please refer to the HBV section of the Guidelines for the Prevention and Treatment of Opportunistic Infections in HIV-Infected Adults and Adolescents.

What Should I Tell My Health Care Provider Before Taking Tenofovir Disoproxil Fumarate?

Before taking tenofovir DF, tell your health care provider:

  • If you are allergic to tenofovir DF or any other medicines.
  • If you have liver problems, including HBV infection.
  • If you have kidney problems.
  • If you have bone problems.
  • If you have any other medical conditions.
  • If you are pregnant or plan to become pregnant. Whether tenofovir DF can harm an unborn baby is unknown. Tenofovir DF should be used during pregnancy only if clearly needed. Talk to your health care provider about possible risks with taking tenofovir DF when pregnant.
  • If you are breastfeeding or plan to breastfeed. Do not breastfeed if you are infected with HIV or are taking tenofovir DF.
  • If you are using hormone-based birth control (such as pills, implants, or vaginal rings). For more information about using birth control and HIV medicines at the same time, view the AIDS_info_ HIV and Birth Control infographic.
  • About other prescription and nonprescription medicines, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Tenofovir DF may affect the way other medicines or products work, and other medicines or products may affect how tenofovir DF works. Taking tenofovir DF together with certain medicines or products may cause serious, life-threatening side effects.

How Should I Take Tenofovir Disoproxil Fumarate?

Tenofovir DF (brand name: Viread) comes in the following forms and strengths:

  • 150-mg tablets
  • 200-mg tablets
  • 250-mg tablets
  • 300-mg tablets
  • Oral powder (40 mg of tenofovir DF per 1 g of powder)

Take tenofovir DF according to your health care provider's instructions.

Tenofovir DF tablets should be swallowed whole and can be taken with or without food. People who are unable to swallow the tablets whole may take the oral powder. Use the provided dosing scoop to measure the oral powder. Mix the oral powder with soft foods that can be swallowed without chewing, such as applesauce, baby food, or yogurt. Take the dose of oral powder right after mixing it. Do not mix the oral powder with liquid.

Always take tenofovir DF in combination with other HIV medicines.

If you take too much tenofovir DF, contact your health care provider or local poison control center (1-800-222-1222) right away, or go to the nearest hospital emergency room.

For more information on how to take tenofovir DF, see the FDA drug label from DailyMed. (DailyMed is a federal website that includes the most recent drug labels submitted to FDA.)

What Should I Do If I Forget a Dose?

If you miss a dose of tenofovir DF, take the missed dose as soon as you remember it. But if it is almost time for your next dose, skip the missed dose and just take your next dose at the regular time. Do not take two doses at the same time to make up for a missed dose.

What Side Effects Can Tenofovir Disoproxil Fumarate Cause?

Tenofovir DF may cause side effects. Most side effects from tenofovir DF are manageable, but a few can be serious. Serious side effects of tenofovir DF include a buildup of lactic acid in the blood (lactic acidosis) and severe liver problems. (See the WARNING box above.)

Other possible side effects of tenofovir DF include:

  • New or worsening kidney problems, including kidney failure.
  • Bone problems, including bone pain, softening, or thinning (osteopenia), which may lead to fractures.
  • Changes in body fat (including gain or loss of fat).
  • Immune reconstitution inflammatory syndrome (IRIS), a condition that sometimes occurs when the immune system begins to recover after treatment with an HIV medicine. As the immune system gets stronger, it may have an increased response to a previously hidden infection.

Tell your health care provider if you have any side effect that bothers you or that does not go away.

These are not all the possible side effects of tenofovir DF. To learn more about possible side effects of tenofovir DF, read the drug label or package insert or talk to your health care provider or pharmacist.

The AIDS_info_ fact sheet on HIV Medicines and Side Effects also includes information that may apply to tenofovir DF.

You can also report side effects to FDA at 1-800-FDA-1088 (1-800-332-1088) or online at

How Should Tenofovir Disoproxil Fumarate Be Stored?

  • Store tenofovir DF at room temperature, 68°F to 77°F (20°C to 25°C).
  • Keep tenofovir DF in the container that it came in and keep the container tightly closed. If the container has a small packet of drying agent (called a desiccant), do not remove it. The desiccant protects the medicine from moisture.
  • Do not use tenofovir DF if the original seal over the container opening is broken or missing.
  • Throw away tenofovir DF that is no longer needed or expired (out of date). Follow FDA guidelines on how to safely dispose of unused medicine.
  • Keep tenofovir DF and all medicines out of reach of children.

Where Can I Find More Information About Tenofovir Disoproxil Fumarate?

More information about tenofovir DF is available:

Manufacturer Information

Gilead Sciences, Inc.
Main number: 800-445-3235
Patient assistance: 800-226-2056

The above Patient Version drug summary is based on the following FDA label(s): Powder, tablet (coated).