Truvada is a prescription drug that treats and helps prevent HIV by blocking an enzyme that allows HIV to replicate. Your response to this drug may vary based on your medical history and diagnosis.
Truvada is used as preexposure prophylaxis (PrEP). This means that it helps prevent HIV in adults and certain adolescents who are at risk of contracting HIV through sexual activity. This drug is also used to treat HIV in adults and certain children. If you take Truvada to treat HIV, you’ll take it with other HIV drugs.
Truvada contains two active ingredients: emtricitabine and tenofovir disoproxil fumarate, both of which belong to a class of medications called nucleoside reverse transcriptase inhibitors (NRTIs).
The way a drug works is known as its mechanism of action. The mechanism of action for Truvada is the same for both treating and preventing HIV — it keeps the virus from being able to replicate (copy itself).
For treating HIV
NRTIs (the drug class Truvada belongs to) work by preventing HIV from replicating and growing in your body. They do this by blocking an enzyme (a type of protein) called reverse transcriptase, which HIV must have to copy itself and grow. As a result, the levels of HIV in your body begin to decrease.
Truvada is used with other antiretroviral medications to treat HIV. You’ll take at least one other antiretroviral drug with Truvada.
Your doctor can provide more information on how Truvada fits into your HIV treatment plan, including which other medication(s) you’ll take with it. Examples of other antiretrovirals that you can use with Truvada include raltegravir (Isentress) and dolutegravir (Tivicay).
For PrEP
When used for HIV PrEP, Truvada works by preventing the virus from replicating in your body after exposure. You should not take Truvada for HIV PrEP if you already have HIV. To treat HIV, Truvada must be used with other medications. Truvada used on its own, is not a complete treatment for HIV.
Your doctor will order an HIV test before prescribing Truvada for you. This is to ensure that you don’t have HIV. You’ll have this test done at least every 3 months for as long as you take Truvada for PrEP.
The medications contained in Truvada begin to work right away to reduce HIV levels. However, it may take 1 to 6 months of treatment before your HIV levels are low enough that they’re no longer detectable in your blood. (This is the goal of treatment — when HIV is no longer detectable, it’s no longer transmissible to another person.)
Ask your doctor or pharmacist if you’d like to learn more about how Truvada works.
Disclaimer: Healthline has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.