Antiretroviral Prophylaxis

Antiretroviral prophylaxis, also known as pre-exposure prophylaxis (PrEP) or post-exposure prophylaxis (PEP), is a medical intervention designed to prevent the transmission of HIV (Human Immunodeficiency Virus) infection.

Pre-Exposure Prophylaxis (PrEP)

PrEP involves taking antiretroviral medications daily to reduce the risk of acquiring HIV infection. The medication typically used for PrEP is a combination of two drugs: tenofovir disoproxil fumarate (TDF) and emtricitabine (FTC). This regimen has been shown to be highly effective in preventing HIV transmission when taken consistently and correctly.

Post-Exposure Prophylaxis (PEP)

PEP involves taking antiretroviral medications as soon as possible after a potential exposure to HIV, such as a needle stick injury or unprotected sex with someone who has HIV. The goal of PEP is to prevent the virus from establishing a permanent infection. The medication regimen for PEP typically consists of a combination of three drugs: TDF, FTC, and a third agent such as lopinavir/ritonavir (LPV/r) or raltegravir (RAL).

How Antiretroviral Prophylaxis Works

Antiretroviral medications work by blocking the replication of HIV, thereby preventing the virus from establishing a permanent infection. When taken as PrEP, these medications create a barrier that prevents HIV from infecting cells in the body. When taken as PEP, the medications help to eliminate any infected cells and prevent the virus from spreading.

Efficacy and Safety

Studies have shown that antiretroviral prophylaxis is highly effective in preventing HIV transmission when taken correctly. PrEP has been shown to reduce the risk of HIV infection by up to 92% in individuals who take the medication consistently. PEP has also been shown to be effective in preventing HIV transmission, with studies demonstrating a significant reduction in the risk of infection when the medication is started promptly after exposure.

The safety profile of antiretroviral prophylaxis is generally good, with most individuals experiencing few or no side effects. Common side effects may include nausea, diarrhea, and headache. However, more severe side effects can occur, such as kidney damage or bone density loss, particularly with long-term use.

Eligibility and Access

Antiretroviral prophylaxis is typically recommended for individuals who are at high risk of acquiring HIV infection, such as those who have multiple sex partners, engage in unprotected sex, or share needles. In the United States, PrEP is approved for use in adults and adolescents who weigh at least 35 kg (77 lbs) and are at high risk of acquiring HIV infection. PEP is available for individuals who have been exposed to HIV, regardless of their risk factors.

Access to antiretroviral prophylaxis may vary depending on the country, region, or healthcare system. In some areas, PrEP and PEP may be covered by insurance or government programs, while in other areas, access may be limited due to cost or availability of the medication.