What to Do If You Are Accidentally Exposed to HIV

If you think that you've been accidentally exposed to HIV, either through sex or other high-risk modes of transmission, there are medications you can take—called post-exposure prophylaxis (PEP)—that can significantly reduce your risk of infection if started in a timely manner.

Examples of high-risk exposure include:

• Unprotected sex
• A condom that has slipped or burst
• Shared needles or other drug paraphernalia
• Rape or sexual assault

What Is PEP?

PEP consists of a 28-day course of antiretroviral drugs that must be taken completely and without interruption. In order to minimize the risk of infection, PEP must be started as soon as possible—ideally within one to 36 hours of exposure.

While PEP can be administered within 72 hours of exposure, the chances of averting an infection are best the sooner you start. The more time that passes, the more the virus is able to migrate from the site of the exposure to nearby cells and tissues.

PEP is also prescribed to healthcare workers who have had occupational exposure to HIV, such as through contact with infected blood or a needle-stick injury.

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Before Treatment

Once you arrive at the hospital or clinic, you will be asked about the exposure incident by a doctor, nurse, or dedicated staff member. Do not be embarrassed to describe what happened. The aim of the interview is to ascertain if the incident poses a viable risk of transmission. This can help you avoid taking drugs you don't actually need.

On the other hand, PEP may not be viable if you have waited too long to seek treatment.

If it is determined that you are at substantial risk of infection, you will be given a rapid HIV test to determine whether you are HIV-positive or HIV-negative.

• If you are HIV-positive, it means that you have HIV. A second test will then be given to confirm the results, after which a trained healthcare worker will discuss your results and explain how HIV is diagnosed and treated.
• If you are HIV-negative, it means there is no evidence of the virus in your blood. The healthcare worker will explain what a negative result does and does not mean and walk you through the steps of PEP.

If PEP is authorized, you will be advised about how to take the drugs, what side effects may occur, and the importance of treatment adherence.

Additional tests may be ordered to screen for sexually transmitted diseases or hepatitis B if needed. Emergency contraception may also be prescribed in cases of rape or sexual assault.

How PEP Is Prescribed

In the past, PEP consisted of either one, two, or three antiretroviral drugs based on the severity of the exposure. Part of the reason for this was that earlier drugs were more toxic and often caused intolerable side effects. Newer-generation antiretrovirals used for PEP are far more tolerable and tend to cause few, if any, side effects.

PEP can be used for both adults and adolescents. The CDC recommends several options, two of which are preferred and an alternate if the preferred drugs aren't available.

A follow-up HIV test would then be scheduled, usually within four to six weeks of the completion of PEP. If the test is negative, you will be counseled on how to reduce your risk of HIV moving forward.

Effectiveness of PEP

The effectiveness of PEP has typically been evaluated in healthcare settings, mainly because risk assessment, treatment, and post-treatment protocols are standardized and the results are more easily tracked.

In non-occupational settings, this is not the case. Not only do the routes of exposure vary, but it is often difficult to assess whether treatment was adhered to, whether the details of the incident were accurate, or whether PEP was even necessary.

With respect to PEP in healthcare settings, an early study published in the New England Journal of Medicine concluded that PEP administered after a percutaneous (needle puncture) wound reduced the risk of HIV by 81%. Subsequent studies suggest the results today may be closer to 90% or greater.

A Word From Verywell

PEP is not a morning-after pill. If you are at high risk of getting HIV, speak with your healthcare provider about a preventive strategy known as pre-exposure prophylaxis (PrEP). Treatment is available as a daily pill (Truvada or Descovy) or as an injection (Apretude) administered every two months. Both options can greatly reduce your risk of getting HIV.