(a def' o veer)

Brand Name(s): Hepsera^®; also available generically

IMPORTANT WARNING:

Do not stop taking adefovir without talking to your doctor. When you stop taking adefovir your hepatitis may get worse. This is most likely to happen during the first 3 months after you stop taking adefovir. Be careful not to miss doses or run out of adefovir. Tell your doctor if you have or have ever had liver disease other than hepatitis B or cirrhosis (scarring of the liver). If you experience any of the following symptoms after you stop taking adefovir, call your doctor immediately: extreme tiredness, weakness, nausea, vomiting, loss of appetite, yellowing of the skin or eyes, dark-colored urine, light-colored bowel movements, and muscle or joint pain.

Adefovir may cause kidney damage. Tell your doctor if you have or have ever had kidney disease, high blood pressure, or diabetes. Tell your doctor and pharmacist if you are taking or have ever taken any of the following medications: aminoglycoside antibiotics such as amikacin, gentamicin, kanamycin, neomycin, streptomycin, and tobramycin (Tobi,); aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (Advil, Motrin) and naproxen (Aleve, Naprosyn); cyclosporine (Gengraf, Neoral, Sandimmune); tacrolimus (Prograf); or vancomycin. If you experience any of the following symptoms, call your doctor immediately: confusion; decreased urination; or swelling of the hands, feet, ankles, or lower legs.

If you have HIV or AIDS that is not being treated with medications and you take adefovir, your HIV infection may become difficult to treat. Tell your doctor if you have HIV or AIDS or if you have unprotected sex with more than one partner or use injectable street drugs. Your doctor may test you for HIV infection before you begin treatment with adefovir and at any time during your treatment when there is a chance that you were exposed to HIV.

Adefovir, when used alone or in combination with other antiviral medications, can cause serious or life-threatening damage to the liver and a condition called lactic acidosis (a build-up of acid in the blood). The risk that you will develop lactic acidosis may be higher if you are a woman, if you are overweight, or if you have been treated with medications for hepatitis B virus (HBV) infection for a long time. Tell your doctor if you have or have ever had liver disease. If you experience any of the following symptoms, call your doctor immediately: confusion; unusual bleeding or bruising; yellowing of the skin or eyes; dark-colored urine; light-colored bowel movements; difficulty breathing; stomach pain or swelling; nausea; vomiting; unusual muscle pain; loss of appetite for at least a few days; lack of energy; flu-like symptoms; itching; feeling cold, especially in the arms or legs; dizziness or lightheadedness; fast or irregular heartbeat; or extreme weakness or tiredness.

Keep all appointments with your doctor and the laboratory before, during, and for a few months after your treatment with adefovir. Your doctor will order certain lab tests to check your body's response to adefovir during this time.

Talk to your doctor about the risks of taking adefovir.

WHY is this medicine prescribed?

Adefovir is used to treat chronic (long-term) hepatitis B infection (swelling of the liver caused by a virus) in adults and children 12 years of age and older. Adefovir is in a class of medications called nucleotide analogs. It works by decreasing the amount of hepatitis B virus (HBV) in the body. Adefovir will not cure hepatitis B and may not prevent complications of chronic hepatitis B such as cirrhosis of the liver or liver cancer. Adefovir may not prevent the spread of hepatitis B to other people.

Are there OTHER USES for this medicine?

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

HOW should this medicine be used?

Adefovir comes as a tablet to take by mouth. It is usually taken once a day with or without food. Take adefovir at around the same time every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take adefovir exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

What SPECIAL PRECAUTIONS should I follow?

Before taking adefovir,

• tell your doctor and pharmacist if you are allergic to adefovir; any other medications; or any of the ingredients in adefovir tablets. 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 or plan to take while taking adefovir. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.

• do not take adefovir if you are pregnant or plan to become pregnant. If you become pregnant while taking adefovir, call your doctor. Do not breastfeed while taking adefovir.

What SPECIAL DIETARY instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What should I do IF I FORGET to take a dose?

If you remember the missed dose on the day that you were supposed to take it, take the missed dose as soon as you remember it. However, if you do not remember the missed dose until the next day, skip the missed dose and continue your regular dosing schedule. Do not take more than one dose of adefovir on the same day. Do not take a double dose to make up for a missed one.

What SIDE EFFECTS can this medicine cause?

Adefovir may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

• weakness
• headache
• diarrhea
• gas
• indigestion
• sore throat
• runny nose
• rash

Adefovir 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).

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

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.

What should I do in case of OVERDOSE?

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

Symptoms of overdose may include the following:

• upset stomach
• stomach discomfort

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.

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.

This report on medications is for your information only, and is not considered individual patient advice. Because of the changing nature of drug information, please consult your physician or pharmacist about specific clinical use.

The American Society of Health-System Pharmacists, Inc. represents that the information provided hereunder was formulated with a reasonable standard of care, and in conformity with professional standards in the field. The American Society of Health-System Pharmacists, Inc. makes no representations or warranties, express or implied, including, but not limited to, any implied warranty of merchantability and/or fitness for a particular purpose, with respect to such information and specifically disclaims all such warranties. Users are advised that decisions regarding drug therapy are complex medical decisions requiring the independent, informed decision of an appropriate health care professional, and the information is provided for informational purposes only. The entire monograph for a drug should be reviewed for a thorough understanding of the drug's actions, uses and side effects. The American Society of Health-System Pharmacists, Inc. does not endorse or recommend the use of any drug. The information is not a substitute for medical care.

AHFS^® Patient Medication Information™. © Copyright, 2024. The American Society of Health-System Pharmacists^®, 4500 East-West Highway, Suite 900, Bethesda, Maryland. All Rights Reserved. Duplication for commercial use must be authorized by ASHP.

Selected Revisions: October 15, 2023.