Taking tenofovir alone or in combination with other antiviral medications may cause life-threatening damage to the liver and a potentially life-threatening condition called lactic acidosis (buildup of lactic acid in the blood). Tell your doctor if you have or have ever had liver disease. If you experience any of the following symptoms, call your doctor immediately or get emergency medical treatment: nausea, vomiting, pain in the upper right part of your stomach, loss of appetite, extreme tiredness, weakness, dizziness, lightheadedness, fast or irregular heartbeat, trouble breathing, dark yellow or brown urine, light-colored bowel movements, yellowing of the skin or eyes, feeling cold, especially in the arms or legs, or muscle pain that is different than any muscle pain you usually experience.
If you have hepatitis B virus infection (HBV; an ongoing liver infection) and you take tenofovir, your condition may suddenly worsen when you stop taking this medication. Tell your doctor if you have or have ever had HBV. Your doctor will examine you and order lab tests regularly for several months after you stop taking this medication to see if your HBV has worsened.
Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests to check your body's response to tenofovir.
Talk to your doctor about the risks of taking tenofovir.
Why is this medication prescribed?
Tenofovir is used along with other medications to treat human immunodeficiency virus (HIV) infection in adults and children 2 years of age and older. Tenofovir is also used to treat chronic (long term) HBV in adults and children 12 years of age and older. Tenofovir is in a class of medications called nucleoside reverse transcriptase inhibitors (NRTIs). It works by decreasing the amount of HIV and HBV in the blood. Although tenofovir will not cure HIV, it may decrease your chance of developing acquired immunodeficiency syndrome (AIDS) and HIV-related illnesses such as serious infections or cancer. Taking these medications along with practicing safer sex and making other life-style changes may decrease the risk of transmitting the HIV virus to other people. Tenofovir will not cure hepatitis B and may not prevent complications of chronic hepatitis B such as cirrhosis of the liver or liver cancer. Tenofovir may not prevent the spread of hepatitis B to other people.
How should this medicine be used?
Tenofovir comes as a tablet and as an oral powder to take by mouth. The tablet is usually taken with or without food once daily. The powder is usually taken with food once daily. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take tenofovir exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.
Tenofovir oral powder must be added to 2 to 4 ounces of soft food such as applesauce, baby food, or yogurt. Stir the mixture with a spoon until well mixed. Consume the mixture right away to avoid a bitter taste. Do not mix tenofovir oral powder with liquid.
Continue to take tenofovir even if you feel well. Do not stop taking tenofovir without talking to your doctor.
Ask your pharmacist or doctor for a copy of the manufacturer's information for the patient.
Other uses for this medicine
This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.
What special precautions should I follow?
Before taking tenofovir,
- tell your doctor and pharmacist if you are allergic to tenofovir, any other medications, or any of the ingredients in tenofovir tablets or oral powder. Ask your pharmacist for a list of the ingredients.
- tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking. Be sure to mention any of the following: antiviral medications such as acyclovir (Zovirax), cidofovir (Vistide), ganciclovir (Cytovene, Vitasert), valacyclovir (Valtrex), and valganciclovir (Valcyte); aspirin and other nonsteroidal anti-inflammatory medications (NSAIDs) such as ibuprofen (Advil, Motrin) and naproxen (Aleve, Naprosyn); gentamicin; other medications for HIV or AIDS including atazanavir (Reyataz, in Evotaz), darunavir (Prezista, in Prezcobix), didanosine (Videx), and lopinavir/ritonavir (in Kaletra). Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
- tell your doctor if you have or have ever had the conditions mentioned in the IMPORTANT WARNING section, HIV, bone problems including osteoporosis (a condition in which the bones become thin and weak and break easily) or bone fractures, or kidney disease.
- tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. If you become pregnant while taking tenofovir, call your doctor. You should not breastfeed if you are infected with HIV or if you are taking tenofovir.
- you should be aware that your body fat may increase or move to different areas of your body, such as your upper back, neck (''buffalo hump''), breasts, and around your stomach. You may notice a loss of body fat from your face, legs, and arms.
- you should know that while you are taking medications to treat HIV infection, your immune system may get stronger and begin to fight other infections that were already in your body. This may cause you to develop symptoms of those infections. If you have new or worsening symptoms during your treatment with tenofovir, be sure to tell your doctor.
What special dietary instructions should I follow?
Unless your doctor tells you otherwise, continue your normal diet.
What should I do if I forget a dose?
Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.
What side effects can this medication cause?
Tenofovir may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
- difficulty falling asleep or staying asleep
- weight loss
Some side effects can be serious. If you experience any of those listed in the IMPORTANT WARNING or SPECIAL PRECAUTIONS sections, call your doctor immediately.
- decreased urination
- ongoing or worsening bone pain
- pain in the in the arms, hands, feet, or legs
Tenofovir may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.
If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).
What should I know about storage and disposal of this medication?
Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).
Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.
In case of emergency/overdose
In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.
What other information should I know?
Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.
Keep a supply of tenofovir on hand. Do not wait until you run out of medication to refill your prescription.
It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.