What you need to know about the ‘other’ little blue pill

by Jesse M. Ehrenfeld, MD, MPH — Director, Vanderbilt Program for LGBTQ Health

Although you may only now be starting to hear and see more about “PrEP,” which stands for pre-exposure prophylaxis, it’s been around as a way to prevent HIV for almost seven years. While you have probably seen commercials for it, or ads in magazines, a lot of people still don’t know exactly what pre-exposure prophylaxis means. So, let’s walk you through the basics.

What is PrEP and how does PrEP work?

Pre-exposure prophylaxis, or PrEP, is a strategy to prevent HIV in those who are at high risk for acquiring HIV. The HIV prevention component is a pill that contains two medications used to prevent HIV transmission. The two medications contained in the pill prevent the establishment of an HIV infection in somebody that is exposed. However, for this to work, you actually have to be taking the medication regularly, seven days a week. When the medication is used as part of an HIV prevention plan, it can dramatically reduce the risk of acquiring HIV.

Will PrEP prevent other sexually transmitted infections (STIs)?

No. PrEP does not prevent other sexually transmitted infections, and this is a key point for anyone that goes on PrEP. It will not prevent the transmission of gonorrhea, chlamydia, or syphilis.

Who should go on PrEP?

Anyone who is at high risk of acquiring HIV should consider going on PrEP. If you think you might be at risk, you should talk to a medical provider about PrEP. People who have an HIV-positive sex partner, a high number of sex partners, a history of sexually transmitted infections, are inconsistent in using condoms, or inject drugs would all be good candidates for PrEP. You must also weigh at least 77 lbs to take the medication.

What are the side-effects of PrEP?

There are a number of minor side-effects that people may notice. The most common side effects are headache (7%), abdominal pain (4%), and weight loss (3%). Based on large studies, side-effects are usually fairly limited and quite tolerable.

There are, however, some important long-term side effects worth considering before starting PrEP. The medication can lead to a loss of kidney function. This is really only an issue for people who have underlying kidney disease or take other medications that affect the kidney. The other long-term side-effect is the loss of bone mineral density.

Where can I get PrEP?

Many primary care providers and walk-in clinics now offer PrEP. Vanderbilt University Medical Center has a PrEP clinic staffed Monday through Friday from 8 am to 5 pm. To make an appointment, you can call (615) 936-1174. You can also go to preplocator.org to find other sites across the country. The Vanderbilt Program for LGBTQ Health can also help you locate a PrEP provider or clinic near you and can be reached at (615) 936-3879 or lgbtq.health@vumc.org.

How much does PrEP cost?

PrEP can be expensive, but the good news is that almost all insurance plans cover the cost of PrEP – including TennCare and Medicare.

What lab testing is required to be on PrEP?

It is important to test you for HIV before starting PrEP. Also, it is important to test for hepatitis and kidney problems and perform a screen for sexually transmitted infections. Once you have started PrEP, it is important to be tested for HIV every three months and have follow-up kidney testing as well, typically once or twice a year.

How often do I have to renew my PrEP prescription?

Because PrEP requires HIV testing and follow-up labs, you should expect to have appointments every three months to refill your prescription.


Developing an HIV Prevention Plan with PrEP

• Know your HIV status and the status of your partners
• Get tested for HIV at least every three months, and regularly for other STIs
• Test for pregnancy and discuss with your doctor if you are planning to become pregnant
• Take your PrEP medication every day (one pill)
• Use safer sex practices like condoms and lube
• See a healthcare provider to monitor your kidney function