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Generic name: brincidofovir
Dosage forms: tablets, oral suspension
Drug class: Purine nucleosides

Medically reviewed by Judith Stewart, BPharm. Last updated on Aug 23, 2023.

What is Tembexa?

Tembexa is a prescription medicine used to treat smallpox disease caused by a type of virus called variola virus in adults, children, and infants.

Before taking Tembexa

Before you start treatment, tell your healthcare provider about all your medical conditions, including if you:

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements. Some medicines interact with Tembexa causing side effects. Keep a list of your medicines to show your healthcare provider and pharmacist.

How should I take Tembexa?

Tembexa side effects

Tembexa may cause serious side effects, including:

The most common side effects include:

Tembexa may cause low sperm counts and affect the ability to conceive children. Talk to your healthcare provider if you have concerns about fertility.
These are not all the possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA 1088.

What other drugs will affect Tembexa?

Other drugs may interact with brincidofovir, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all other medicines you use.

How should I store Tembexa?

Keep all medicines out of the reach of children and pets.

General information about the safe and effective use of Tembexa.

Medicines are sometimes prescribed for purposes other than those listed in a Patient Information leaflet. Do not use this medicine for a condition for which it was not prescribed. Do not give it to other people, even if they have the same symptoms that you have. It may harm them. You can ask your pharmacist or healthcare provider for information that is written for health professionals.

What are the ingredients in Tembexa?

Active ingredient: brincidofovir
Inactive ingredients:

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.