Tenofovir alafenamide

(ten of' oh vir al" a fen' a mide)

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

IMPORTANT WARNING:

If you have hepatitis B virus infection (HBV; an ongoing liver infection) and you take tenofovir alafenamide (AF), your condition may suddenly worsen when you stop taking this medication. Be careful not to miss doses or run out of tenofovir AF. Your doctor may test you to see if you have HBV before you begin your treatment with tenofovir AF. Your doctor will examine you and order lab tests regularly for several months after you stop taking this medication. Tell your doctor if you experience any new or unusual symptoms after you stop taking tenofovir AF.

Keep all appointments with your doctor and the laboratory.

Talk to your doctor about the risks of taking tenofovir.

WHY is this medicine prescribed?

Tenofovir alafenamide (AF) is used to treat chronic (long term) hepatitis B virus (HBV) infection. Tenofovir is in a class of medications called nucleoside reverse transcriptase inhibitors (NRTIs). It works by decreasing the amount of HBV in the blood.

Tenofovir AF will not cure hepatitis B and may not prevent complications of chronic hepatitis B. Tenofovir AF 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?

Tenofovir AF comes as a tablet to take by mouth. Take with food once daily. Take tenofovir AF at around the same time every day.

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 AF even if you feel well. Do not stop taking tenofovir without talking to your doctor. If you stop taking tenofovir AF even for a short time, or skip doses, the virus may become resistant to medications and may be harder to treat.

Ask your pharmacist or doctor for a copy of the manufacturer's information for the patient.

What SPECIAL PRECAUTIONS should I follow?

Before taking tenofovir AF,

• tell your doctor or pharmacist if you are allergic to this drug, any part of this drug, or any otherdrugs, foods or substances. Tell your doctor or pharmacist about the allergy and whatsymptoms you had.

• tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.

• the following nonprescription and herbal products may interact with tenofovir AF: St. John's wort and nonsteroidal anti-inflammatory drugs (NSAIDS) such as aspirin, ibuprofen (Advil^®, Motrin^®, others) and naproxen (Aleve^®). Be sure to let your doctor and pharmacist know that you are taking these medications before you start taking tenofovir AF. Do not start these medications whiletaking tenofovir AF without discussing with your healthcare provider.

• tell your doctor if you have or have ever had liver disease (other than hepatitis B), or kidney disease.

• tell your doctor if you have or ever had HIV. If you have HIV that is not being treated with medications and you take tenofovir, your HIV infection may become more difficult to treat. Your doctor may test you for HIV before you begin your treatment.

• tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. If you become pregnant while taking tenofovir, call 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 to take 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 medicine cause?

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

• headache

Some side effects can be serious. If you experience any of these symptoms or those listed in the IMPORTANT WARNING or SPECIAL PRECAUTIONS sections, call your doctor immediately.

• decreased urination
• swelling of feet and ankles
• pain in the arms, hands, feet, or legs
• extreme tiredness or weakness; nausea; vomiting; loss of appetite; yellowing of the skin or eyes; dark-colored urine; light-colored bowel movements; pain in upper right part of your stomach
• weakness, tiredness, unusual muscle pain, stomach pain with nausea and vomiting, dizziness or lightheadedness, fast or irregular heartbeat, shortness of breath or fast breathing, cold or blue-colored hands and feet

Tenofovir AF 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 (https://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).

Keep all medication out of sight and reach of children as many containers are not child-resistant. Always lock safety caps. Place the medication in a safe location – one that is up and away and out of their sight and reach. https://www.upandaway.org

Dispose of unneeded medications in a way so that pets, children, and other people cannot take them. Do not flush this medication down the toilet. Use a medicine take-back program. Talk to your pharmacist about take-back programs in your community. Visit the FDA's Safe Disposal of Medicines website https://goo.gl/c4Rm4p for more information.

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.

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 AF on hand. Do not wait until you run out of medication to refill your prescription.

Keep a written list of all of the prescription and nonprescription (over-the-counter) medicines, vitamins, minerals, and dietary supplements you are taking. Bring this list with you each time you visit a doctor or if you are admitted to the hospital. You should carry the list 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, 2025. 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: July 15, 2025.