Post-exposure HIV prophylaxis
Summary
Definition
History and exam
Key diagnostic factors
- exposure to HIV within past 72 hours
- breakage, slippage, or nonusage of a condom
- history of ejaculation from source
- trauma or skin break
- genital ulcers
- source from high-risk group for HIV viremia
- source from geographic area with high HIV prevalence
- high-risk sexual history in exposed person
- detectable HIV viral load in source
Other diagnostic factors
- history of negative HIV test in source
- source with hepatitis coinfection
- antiviral HIV resistance in source
- current prescription or nonprescription drugs
- history of drug allergies
- flu-like illness
Risk factors
- blood transfusion from donor living with HIV
- receptive anal intercourse
- injection drug use and needle sharing
- percutaneous (needlestick) injury
- insertive anal intercourse
- receptive penile-vaginal intercourse
- insertive penile-vaginal intercourse
- insertive or receptive oral intercourse
Diagnostic investigations
1st investigations to order
- fourth-generation HIV antigen/antibody enzyme-linked immunosorbent assay (ELISA)
- HIV nucleic acid test
- renal function tests
- liver function tests
- hepatitis B serology
- hepatitis C serology
- pregnancy test
- screening for other sexually transmitted infections (STIs)
Investigations to consider
- HIV viral load (if symptoms of HIV seroconversion)
Treatment algorithm
adults or adolescents ≥12 years: nonpregnant
pregnant or breastfeeding
children
Contributors
Authors
Julie Fox, BSc(Hons), MBChB, MRCP, MD
HIV consultant and Honorary Senior Lecturer KCL
Department of HIV
Harrison Wing
Guy’s and St Thomas Hospital NHS Foundation Trust
London
UK
Disclosures
JF declares that she has no competing interests.
Acknowledgements
Dr Julie Fox would like to gratefully acknowledge Dr Ming Jie Lee, Dr Jennifer A. Johnson, Dr Paul Sax, Dr Rebecca Plank, Dr Michael Brady, Dr Emily Cheserem, and Dr Claire M. Naftalin, the previous contributors to this topic.
Disclosures
MJL has received consulting fees from Thriva Ltd. and conference reimbursement from Gilead Sciences, Inc., and travel grants from ViiV Healthcare, not related to this work. JAJ declares that she has no competing interests. PS serves as a consultant for Abbott, BMS, Gilead, GSK, Merck, and Janssen. He receives grant support from BMS, Gilead, and GSK. EC has been sponsored by GlaxoSmithKline for several conferences and sponsored by Gilead Sciences, Bristol-Myers Squibb Pharmaceuticals, and Abbott Laboratories to attend various educational programs. CMN has been sponsored by Bristol-Myers Squibb Pharmaceuticals to attend an educational program. CMN is an author of a reference cited in this topic. MB not disclosed. RP declares that she has no competing interests.
Peer reviewers
Professor Margaret Johnson, MB BS, MD, FRCP
Clinical Director
HIV/AIDS Services
Royal Free Hampstead NHS Trust
London
UK
Disclosures
MJ declares that she has no competing interests.
William Rodriguez, MD
Chief Medical Officer
Foundation for Innovative New Diagnostics (FIND)
Campus Biotech
Geneva
Switzerland
Disclosures
Not disclosed.
Peer reviewer acknowledgements
BMJ Best Practice topics are updated on a rolling basis in line with developments in evidence and guidance. The peer reviewers listed here have reviewed the content at least once during the history of the topic.
Disclosures
Peer reviewer affiliations and disclosures pertain to the time of the review.
References
Key articles
World Health Organization. Guidelines for HIV post-exposure prophylaxis. Jul 2024 [internet publication].Full text
British Association for Sexual Health and HIV. Post-exposure prophylaxis. Sep 2021 [internet publication].Full text
Tanner MR, O'Shea JG, Byrd KM, et al. Antiretroviral postexposure prophylaxis after sexual, injection drug use, or other nonoccupational exposure to HIV - CDC recommendations, United States, 2025. May 2025 [internet publication].Full text Abstract
Kofman AD, Struble KA, Heneine W, et al. 2025 US Public Health Service guidelines for the management of occupational exposures to human immunodeficiency virus and recommendations for post-exposure prophylaxis in healthcare settings. Infect Control Hosp Epidemiol. 2025 Sep;46(9):863-73.Full text Abstract
Reference articles
A full list of sources referenced in this topic is available to users with access to all of BMJ Best Practice.
Guidelines
- Antiretroviral postexposure prophylaxis after sexual, injection drug use, or other nonoccupational exposure to HIV - CDC recommendations, United States, 2025
- Guidelines for HIV post-exposure prophylaxis
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