PEP: urgent prevention after possible HIV exposure

After a possible significant HIV exposure, seek medical assessment immediately — ideally within the first 24 hours and no later than 72 hours. If you cannot get a quick response from a consultant, contact an emergency department or infectious diseases clinic. Do not wait for an appointment, payment confirmation or an online form response. In immediate danger or serious illness, call 112.

Post-exposure prophylaxis is a course of antiretroviral medicines after certain possible HIV exposures. It aims to prevent infection becoming established. It is not a vaccine, treatment for already confirmed HIV, or protection against every sexually transmitted infection. Assessment determines whether the benefits justify taking it.

After certain sexual exposures, a broken condom, shared injecting equipment, or contact between a mucous membrane/broken skin and potentially infectious fluid. Not every sexual contact or unknown status requires PEP. The exposure type, timing, fluid, partner’s situation and prevention used all matter.

Give the exact or approximate date and time, type of exposure, condom use and any missed PrEP doses. If known, mention the partner’s HIV status and viral load, without delaying care to find documents. Mention medicines, allergies, kidney/liver conditions and possible pregnancy.

A person who maintains an undetectable viral load on treatment does not sexually transmit HIV. A positive diagnosis alone does not automatically mean PEP is needed. If viral load or adherence are unknown, a clinician assesses the situation. Do not postpone first contact with a medical team while trying to clarify everything yourself.

Correctly used PrEP may mean additional PEP is unnecessary. The decision depends on the medicine, regimen, recent doses and exposure. Bring the packaging or medicine name. Do not add tablets from different regimens yourself or double doses as improvised prevention.

PEP works best when started early. The 72-hour limit is not a reason to wait until the third day. If more time has passed, still seek consultation about testing and future prevention, but do not assume standard PEP will be prescribed. With repeated exposures, include the time of the most recent one.

An HIV test and assessment of kidney/liver function, hepatitis and other infections are usually performed according to exposure; a pregnancy test is added when indicated. The baseline HIV test cannot rule out infection from an exposure that has just happened. If PEP is indicated, pending laboratory results must not delay the first dose.

The standard course lasts 28 days. A clinician selects the medicines, considering interactions and health conditions. Plan how to obtain the full course and when the first follow-up conversation will happen. Do not stop simply because you feel well or an early test is negative.

Follow the written instructions for your particular regimen and contact the team promptly. Do not take an arbitrary double dose. Mild nausea or stomach discomfort can be managed; persistent vomiting, rash or other significant symptoms need assessment. Changing the regimen may be possible instead of stopping on your own.

Follow-up is part of the course. CDC 2025 recommends laboratory antigen/antibody testing and HIV NAT at around 4–6 weeks and finally around 12 weeks after exposure, with qualifications for particular situations. The care team adapts the plan to available tests and the local protocol. PrEP/PEP can delay detection, so an early negative test does not end follow-up.

PEP does not provide universal protection for new exposures. Use condoms/barriers and do not share injecting equipment; discuss a new exposure with the team. Symptoms also require assessment for other infections. Continue planned HIV tests even if the course ended without problems.

If future exposures are likely, discuss PrEP while taking PEP. With appropriate assessment and HIV testing, transition can happen immediately after the course. This does not remove the need for subsequent HIV testing. The aim is sustainable prevention that fits your life.

You deserve calm, respectful help. Medical assessment can include PEP, injury care, other infections and emergency contraception when indicated. You do not need to describe what happened perfectly to seek help. If there is immediate danger, first move to a safe place and seek urgent support.

See the PEP consultation page for the current online format and conditions. Payment and administrative steps must not delay urgent medical assessment or the first dose when indicated. If the team is not immediately available, seek an infectious diseases clinic or emergency department.

Write down the exposure time and bring your current medicines or a list of their names. Do not lose time trying to calculate an exact risk percentage from an online table. If the first service does not provide PEP, ask for immediate referral. An available online consultation does not automatically mean the medicine is supplied at the same place.

At the start, the question is whether the exposure requires PEP and how to start in time. During the course, it is how to complete treatment and address difficulties. Afterwards, it is which follow-up tests complete assessment and what prevention suits you next. Written dates help keep these steps distinct.

A negative baseline test does not prove that the exposure that just happened was safe. A positive baseline test also does not prove infection came from that exposure. The medical team therefore considers timing, previous results and confirmatory testing together. Do not stop or change medicines based solely on your own reading of one result.