How Many Days of PrEP Can You Miss?

Key Takeaways

However, correct use is crucial to ensure maximum protection. But what happens if you accidentally miss a day or more of your medication? In this article, we'll explore how many days of PrEP someone can miss and still be protected against HIV.

What is PrEP?

PrEP stands for pre-exposure prophylaxis and is a medication taken before potential exposure to HIV. It contains two drugs that block HIV from taking hold and replicating in the body's cells. 

PrEP is highly effective when taken consistently as directed, reducing the risk of HIV transmission by up to 99%.

How Does PrEP Work?

PrEP works by targeting and blocking the specific pathways that HIV uses to establish infection in the body. 

When PrEP is present in the body, the virus cannot replicate and spread to other cells, even if it is introduced into the system. This significantly reduces the risk of HIV transmission, especially when taken consistently as directed. 

How Many Days of PrEP Can You Miss?

Ideally, you should take PrEP daily to ensure maximum protection against HIV. However, missing one or two days of PrEP may not immediately affect protection against the virus. 

PrEP has a reasonably long half-life, so it remains in the body long enough to have some protective effect even after missing a dose. One dose of PrEP will not significantly affect protection as long as the next dose is taken as scheduled.

On the other hand, if someone misses multiple doses of PrEP, the level of protection may decrease, and their risk of HIV transmission after exposure can increase. If you prefer not to take PrEP every day, an on-demand PrEP schedule might be better suited to your lifestyle. 

Also known as a 2-1-1 schedule, it involves taking two doses between 4 and 24 hours before an exposure, then one dose per day until one day after the last exposure. For some, this is a more convenient alternative to daily PrEP, with less need to worry about taking a daily dose.

Can You Skip PrEP for a Day?

While skipping one day of PrEP is not ideal, it is not an immediate cause for alarm. If you miss a day, or even a few days, of PrEP, your should take your next dose as soon as possible and continue taking PrEP as directed. 

However, you frequently miss doses or forget to take your medication. In that case, consider speaking to your healthcare practitioner about establishing a more effective medication routine.

It's crucial to note that PrEP is not a one-time preventive measure. This medication requires consistent use to maintain maximum protection against HIV. Skipping PrEP for even one day can impact its effectiveness, so it's important to take PrEP as directed.

Key Takeaways

PrEP is a highly effective medication for preventing HIV transmission when taken consistently and as directed. Missing one dose of PrEP won't dramatically reduce the protection conferred by the drug as long as the next dose is taken as scheduled. 

However, missing multiple doses of PrEP can decrease its effectiveness and increase the risk of HIV transmission. It is important to take PrEP as directed and speak to a healthcare practitioner if experiencing difficulties with medication adherence.


Can I miss PrEP one day?

Missing PrEP for one day is not likely to dramatically decrease your protection from HIV. If you miss a day, take your next dose as planned and continue taking it daily. 

What happens if I miss two days of PrEP

Missing two days of PrEP is not recommended, but you will still likely have some protection against HIV. Take your next dose as planned, and talk to your healthcare practitioner if you have trouble sticking to a daily PrEP schedule. 

How long does PrEP protect after stopping?

PrEP may offer some protection for the week after stopping, but the protection will continually decrease. You should not consider yourself protected about stopping PrEP. 

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