PrEP FAQ

Key Takeaways

What is PrEP?

PrEP is pre-exposure prophylaxis for HIV. It’s a daily pill that reduces the risk of contracting HIV by up to 99% when taken as prescribed. The two medications used for PrEP are Truvada (brand and generic) and Descovy (brand only).

How long does it take PrEP to work?

Protection for receptive anal sex begins seven days after taking daily PrEP. For the first week, please use barrier protection (like condoms). For vaginal sex or drug usage, please wait 21 days for maximum protection.

Are there side effects to PrEP?

PrEP may cause short-term side effects like nausea or stomach upset, diarrhea, or headaches. Most side effects resolve within one week. Please discuss with your healthcare practitioner if you are having side effects.

Long-term, PrEP may cause a decrease in bone mineral density or kidney function. We will check your blood work every three months to monitor efficacy and kidney function. If there are any issues, your healthcare practitioner will advise and help you manage this.

How effective is PrEP?

PrEP is approximately 99% effective when taken daily as prescribed. If you miss doses, PrEP is less effective. If you become infected with HIV while you’re taking PrEP, you are at risk of developing HIV mutations that can make HIV more complex to treat. This is another reason why we monitor your labs and regular HIV tests so carefully at Felix.

When can I stop PrEP?

Most experts recommend waiting a full 28 days after your last possible HIV exposure before stopping PrEP.

What if I miss a tablet?

Make sure to take the missed dose as soon as you remember. However, if it’s less than 12 hours before the next dose, skip the missed dose and take your next dose as scheduled. Your protection may be slightly decreased with missed doses. We suggest setting an alarm on your phone or associating your PrEP dose with something you do every day, like brushing your teeth.

What routine lab tests should I have while on PrEP?

Before you start PrEP, your Felix healthcare practitioner will prescribe the following lab tests:

HIV test
Kidney Function Test
Hepatitis B test
Liver Function Test
Pregnancy Test (if applicable)

Your healthcare practitioner will have you complete lab work for HIV after one month on PrEP and every three months after. This will confirm that you are negative for HIV and that the PrEP therapy is working. It is critical that you get these labs done on time, as it can interfere with your medication prescription if the necessary lab work is not available to your practitioner.