Tenofovir (patient information)

# IMPORTANT WARNING:
Tenofovir, when used alone or in combination with other antiviral medications, may cause serious damage to the liver and a condition called lactic acidosis. Tell your doctor if you drink large amounts of alcohol and if you have or have ever had liver disease.
If you experience any of the following symptoms, call your doctor immediately: upset stomach, loss of appetite, excessive tiredness, weakness, dark yellow or brown urine, unusual bleeding or bruising, flu-like symptoms, yellowing of the skin or eyes, and pain in the upper right part of your stomach.
Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests to check your body's response to tenofovir.

# Why is this medication prescribed
Tenofovir is used in combination with other antiviral medications to treat human immunodeficiency virus (HIV) in patients with acquired immunodeficiency syndrome (AIDS). Tenofovir is in a class of antiviral medications called reverse transcriptase inhibitors. It works by slowing the spread of HIV in the body. Tenofovir is not a cure and may not decrease the number of HIV-related illnesses. Tenofovir does not prevent the spread of HIV to other people.

# How should this medicine be used
Tenofovir comes as a tablet to take by mouth. It is usually taken once a day with a meal. 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.
Continue to take tenofovir even if you feel well. Do not stop taking tenofovir without talking to your doctor.

# 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 or any other medications.
- 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 antiinflammatory medications (NSAIDs) such as indomethacin (Indocin); didanosine (Videx); diuretics ('water pills'); penicillin (Pen Vee K, Veetids, others); and probenecid (Benemid). Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
- if you are taking didanosine (Videx), take it 1 hour before or 2 hours after tenofovir.
- in addition to the condition listed in the IMPORTANT WARNING section, tell your doctor if you have or have ever had kidney disease.
- tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking tenofovir, call your doctor. You should not breastfeed while taking tenofovir.
- you should be aware that your body fat may increase or move to different areas of your body, such as your breasts and your upper back.

# 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.

# Side effects

## Mild side effects
Tenofovir may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
- upset stomach
- diarrhea
- vomiting
- gas
- loss of appetite

## Severe side effects
Some side effects can be serious. If you experience any of those listed in the IMPORTANT WARNING section, call your doctor immediately.
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  or by phone .

# What storage conditions are needed for this medicine
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). Throw away any medication that is outdated or no longer needed. Talk to your pharmacist about the proper disposal of your medication.

# 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.

# Brand names
- Viread

# Brand names of combination products
- Atripla  containing Efavirenz, Emtricitabine, and Tenofovir
- Truvada containing Tenofovir and Emtricitabine