So, what is PrEP?

PrEP is a daily pill that if taken regularly offers up to 99% protection from HIV, the virus that causes AIDS.

What is the difference between PrEP and nPEP?

PrEP (Pre-Exposure Prophylaxis):

Is a single pill, brand named Truvada®, taken once daily to provide enough concentration of medicine in your system so that if you become exposed to the virus it will prevent the virus from growing into an infection.

nPEP (Non-Occupational Post-Exposure Prophylaxis):

Is an emergency use of medicine, typically 2-3 pills taken daily for a month, that must be started less than 72 hours after an exposure to HIV.  Rapid start of nPEP therapy will prevent the virus from growing into an infection.

If you think you have been recently exposed to HIV time is of the essence.

Contact us immediately, visit your provider immediately, or seek emergency services at one of these state nPEP enrolled sites to assess eligibility and get started on nPEP.

Why do it daily?

PrEP, like any medicine, only works if you take it. It is critical to have enough medicine in your system to ensure that it is protecting you from HIV. For now, the only way to be sure of that is to do it daily. One pill, once a day to be protected from HIV – not a bad deal.

Who Is It For?

PrEP is for anyone who is not infected with HIV and who is at risk of acquiring HIV.   The partners of HIV positive individuals, men who have sex with men, heterosexual women in high-risk networks, people who inject drugs, transgender women, sex workers and their partners, and anyone having frequent condomless sex or who has had a recent STI of any kind should really consider adding PrEP to their daily routine.

What does it cost?

PrEP is expensive, but there are ways get it paid for regardless of your insurance. There may be costs associated with deductibles and co-payments. Choosing an insurance plan with a lower deductible, such as a silver or gold plan, can help reduce annual costs. For co-payments, take advantage of Gilead’s Co-Payment Assistance Plan. If you do not have insurance or have trouble paying, you can still access PrEP. My PrEP Experience has a handy resource monitoring insurance and Medicaid coverage of Truvada® for PrEP. You can also Contact our health navigators who will describe the options available to you here in Massachusetts.

Are there side effects?

In short, for most people there is some minor stomach discomfort when you first start it and beyond that protection from HIV is the biggest side effect from taking this pill every day.

There is a difference between side effects, which are small things that go away mostly on their own, and adverse effects, which are large things that require an intervention to stop or correct.

We have spoken with many PrEP users and the consensus of most is that there were almost no side effects.  In a small number of people there is some gastrointestinal discomfort (e.g. gas, bloating nausea) or dizziness when starting PrEP.  For those who do experience discomfort it nearly always goes away after about a month. Contact us if you experience discomfort and we will help you get through this start-up period.

In terms of adverse effects, there is a concern that PrEP may worsen the condition of people with existing kidney or bone problems. Your physician will want to test your kidney function before starting PrEP and will want to do regular monitoring to make sure there is no change.  If there is a change, your physician will recommend stopping the use of PrEP, which in all cases observed corrected the adverse effect.

Many common over the counter medications, if used incorrectly or by people with certain conditions, can have more dangerous adverse effects than occur from the daily use of PrEP.  Since PrEP is used under the advisement of and with regular monitoring by a physician, these concerns are well managed.

What About Condoms?

PrEP and condoms have been called the belt and suspenders of HIV prevention. PrEP and condoms can be used together for extra support. But even if condoms are not present during intercourse, because they weren’t available or were forgotten, or because there was an accident or it broke, or because you and your partner(s) just prefer not to use them, with daily use of PrEP you are still protected from HIV. It is important to know that Truvada® as PrEP will not provide protection from other STIs such as syphilis, chlamydia, or gonorrhea. Frequent anal and throat swabs and urine or vaginal testing for these STIs, followed by careful use of antibiotics when present, is your best bet to identify, treat, and prevent the spread of these infections.

Does it start working immediately?

PrEP does not work instantly after taking the first pill.  Your body must build up a high enough concentration of medicine to be effective at blocking HIV. This is known as loading doses.

If you are having receptive anal sex or “bottom”, you need to take the pill every day for one week, then continue taking the pill everyday to maintain that high protective level.  

If you are having receptive vaginal sex, you need to take the pill every day for three weeks, then continue taking the pill everyday to maintain that high protective level.

Sorry ladies.  The reason for the difference is that medicine does not deposit in all parts of the body in the same way and this medicine deposits in the anus more rapidly then it does in the vagina.

What if I have more questions?

We are glad that you want to know more. If you have more questions please contact our heath navigators who will be able to help address all of them.

There are also lots of resources available on the web. The San Francisco AIDS Foundation has created a very detailed Q&A page on their website  For more Q&A please visit their site and then contact us for answers to all of your questions specific to Massachusetts.

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