Truvada clears from the bloodstream within 2 to 5 days, but may remain present in cells for 7 to 10 days. Taking it once a day is important for it to be effective.
Truvada is a prescription medication you use for preexposure prophylaxis (PrEP) to reduce the risk of getting HIV through sex. It is also a treatment for HIV-1. It’s a combination pill containing two active medications: emtricitabine and tenofovir disoproxil fumarate. It works by blocking the HIV virus from replicating in your cells.
Truvada is around 99% effective when you take it as prescribed. To be effective, you have to take Truvada consistently to build up sufficient levels in your system. Unlike a vaccine, it does not stay in your body permanently.
Understanding how long Truvada stays in your system is essential for knowing when you’re protected and what happens if you stop taking it.
The amount of time Truvada stays in your system depends on its half-life. The half-life of a drug is the time it takes for the amount in your body to reduce by 50%. Typically, the body eliminates
The half-lives of the two active medications in Truvada are:
- Emtricitabine: around 10 hours
- Tenofovir: around 7 hours
Because these half-lives are relatively short, the drug doesn’t linger in your body for long after a single dose. This is why you need to take it every 24 hours.
If you miss a dose, the drug levels in your blood and tissues begin to drop. While your body eliminates it relatively quickly, the protective effects inside your cells can last slightly longer. However, they still rely on that daily refill to stay at maximum strength.
If you were to stop taking Truvada completely, protection from HIV will decrease over
Because the drug clears out fairly fast, missing doses can increase your risk of HIV infection.
If you decide to stop PrEP, doctors usually recommend a “wash-out” or continuation period.
If you have had a recent potential exposure to HIV, you should continue taking Truvada for 28 days after the last exposure. This ensures that if any virus entered your body during that last sexual encounter, the medication is still present long enough to stop the infection from taking hold.
Stopping Truvada for people with Hepatitis B
In people with hepatitis B (HBV), stopping Truvada can cause the hepatitis virus to flare up, leading to liver problems. Therefore, you shouldn’t stop taking it without talking with a healthcare professional.
Truvada doesn’t work instantly the moment you swallow the first pill. It takes time for the medication to build up in your body’s tissues. The time it takes to reach maximum protection depends on the type of sexual activity.
- Receptive anal sex: It takes
about 7 days of daily use for Truvada to reach maximum protective levels in rectal tissue. - Receptive vaginal sex and injection drug use: It takes about 21 days of daily use for the drug to reach maximum protective levels in vaginal tissue and blood.
- Insertive vaginal and anal sex: No specific data is available to say when a person who inserts their penis into a vagina or anus will be protected after taking Truvada.
Not everyone processes medication at the same speed. The main way Truvada leaves your system is through your kidneys. Your body eliminates it through your urine.
Your kidney function can affect how long the drug stays in your system. If a person has kidney impairment, the drug effectively stays in the body longer because the kidneys are slower at removing it.
While keeping the drug in the system might sound good for protection, if levels get too high, it can be toxic. Therefore, people with reduced kidney function may need to adjust how often they take the medication, such as taking it every 48 hours instead of every 24 hours, to prevent dangerous buildup.
Because of this, doctors will test your kidneys before you start PrEP and regularly while you are on it to ensure your body is processing the drug safely.
Truvada is a daily medication used to prevent and treat HIV. You must take Truvada daily to build up protective levels, which takes about 7 days for anal sex and up to 21 days for vaginal sex. Once you stop taking the pill, protection fades significantly within 7 to 10 days.
Because the medication is cleared through your kidneys, your kidney health determines how fast the drug leaves your system. Always consult a doctor before stopping PrEP, especially to ensure you are covered for any recent exposures.