Is PrEP Effective After 2 Days?

Key Takeaways

However, many users have questions about the level of protection provided when just starting PrEP. If you're wondering how soon it's safe to be exposed to HIV after starting daily PrEP, read on.

What is PrEP?

PrEP is a medication designed to be taken regularly to protect against infection from HIV. you can take it on a daily schedule or on occasion following the on-demand protocol. When taken on-demand, users take a double dose the day before an exposure, followed by a dose per day until one day after the exposure.

How does PrEP work?

PrEP consists of two active drugs that work by blocking an enzyme required by HIV in order to proliferate in the body's cells. When taken correctly, PrEP dramatically reduces the risk of becoming infected after exposure to HIV by as much as 99%.

HIV replicates itself with the help of a specialized type of white blood cell called a t-cell. When you take PrEP as directed, this process is interrupted, meaning that even if you are regularly exposed to the virus, it is very unlikely for HIV transmission to take place. 

Is PrEP effective after two days?

PrEP can be effective after two days when taken according to the on-demand schedule. While daily PrEP requires taking the same single dose at roughly the same time daily for a week to reach maximum protection, on-demand PrEP is an option if you need the medication to be effective sooner.

This way of taking PrEP is also called the 2-1-1 schedule, which refers to the number of doses taken daily. Two doses are taken anywhere from 4 to 24 hours prior to exposure to HIV. Then, a single dose is taken every day until one day after the last exposure. This can reduce the risk of HIV infection by about 86%.

If taking the regular one-a-day PrEP, there will be some protection after two days, but it will be lower than the 99% maximum protection that is reached after about a week. If you just started taking daily PrEP, it's best not to consider yourself fully protected just yet.

Where to get PrEP

PrEP is available by prescription in Canada. You can obtain it through pharmacies with a prescription and from some community-based organizations or clinics. You can get PrEP mailed to your door by ordering online with Felix. Not missing doses is vital to achieving the full protective effect of PrEP, and scheduling your deliveries can be an excellent way to make sure you always stay supplied. 

If you want to take PrEP, speak to a healthcare practitioner about your options and what is best for your lifestyle.

Key takeaways

When taken as directed, PrEP can reduce the risk of HIV transmission by up to 99%. However, this level of protection is only achieved when taken daily for at least a week. Taking PrEP for at least two days before potential exposure to HIV can still provide some degree of protection against the virus, but it won't be as high as 99%.

Taking PrEP according to the 2-1-1 schedule is a good option if you need the medication to be effective in 2 days. It's important to note that this won't be quite as effective as daily PrEP, but it can still dramatically reduce the risk of infection.

Frequently asked questions

Can I take PrEP after five days?

Taking PrEP five days after an HIV exposure will not be effective. As a pre-exposure form of prophylaxis, PrEP must be taken before HIV exposure to work. Maximum protection is achieved after a week of taking PrEP.

How long does it take for PrEP to be effective for tops?

PrEP takes a week to be fully effective for both tops and bottoms. While the risk of HIV transmission is higher for bottoms, this doesn't mean that tops aren't also at risk.

How quickly is PrEP effective?

PrEP can start conferring some protection after a couple of days, but it will not reach its whole level of 99% efficacy until one week of use.

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