Tenofovir alafenamide/Selected P-gp Inducers; Phenobarbital Interactions
This information is generalized and not intended as specific medical advice. Consult your healthcare professional before taking or discontinuing any drug or commencing any course of treatment.
Medical warning:
Moderate. These medicines may cause some risk when taken together. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.
How the interaction occurs:
Some medicines may lower the amount of tenofovir alafenamide in your blood.
What might happen:
The amount of tenofovir alafenamide in your blood may decrease and it may not work as well.
What you should do about this interaction:
Make sure your healthcare professionals (e.g. doctor and pharmacist) know that you are taking tenofovir alafenamide together with apalutamide, carbamazepine, fosphenytoin, lorlatinib, phenobarbital, phenytoin, primidone, rifabutin, rifampin, rifapentine, or St. John's wort, or if you have taken these medicines in the previous week, or if you stopped taking any of these medicines recently. Your doctor may want to change you to a different medication or adjust the dose of your tenofovir alafenamide.Your healthcare professionals may already be aware of this interaction and may be monitoring you for it. Do not start, stop, or change the dosage of any medicine before checking with them first.
- 1.Descovy (emtricitabine, tenofovir alafenamide) EMA Summary of Product Characteristics. Gilead Sciences Ireland UC December 10, 2018.
- 2.Vemlidy (tenofovir alafenamide fumarate) UK Summary of Product Characteristics. Gilead Sciences Ltd October, 2021.
- 3.Descovy (emtricitabine and tenofovir alafenamide) US prescribing information. Gilead Sciences, Inc. January, 2022.
- 4.Vemlidy (tenofovir alafenamide) US prescribing information. Gilead Sciences, Inc. August, 2020.
- 5.Cerrone Maddalena, Alfarisi Omamah, Neary Megan, Marzinke Mark A, Parsons Teresa L, Owen Andrew, Maartens Gary, Pozniak Anton, Flexner Charles, Boffito Marta. Rifampicin effect on intracellular and plasma pharmacokinetics of tenofovir alafenamide. 2019 Jun;74(6):1670-1678.
- 6.This information is based on an extract from the Certara Drug Interaction Database (DIDB) Platform, Copyright Certara 1999-2023..
Selected from data included with permission and copyrighted by First Databank, Inc. This copyrighted material has been downloaded from a licensed data provider and is not for distribution, except as may be authorized by the applicable terms of use.
CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgment of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse effects, nor should it be construed to indicate that use of a particular drug is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any drug, changing any diet or commencing or discontinuing any course of treatment.