View source for Post-exposure prophylaxis

{{Short description|Preventive medical treatment after exposure}}
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'''Post-exposure prophylaxis''', also known as '''post-exposure prevention''' ('''PEP'''), is any [[Preventive medicine|preventive medical]] treatment started after exposure to a [[pathogen]] in order to prevent the infection from occurring.

It should be contrasted with [[pre-exposure prophylaxis]], which is used before the patient has been exposed to the infective agent.

==COVID-19==
In 2021, the US [[FDA]] gave [[emergency use authorization]] (EUA) to [[bamlanivimab/etesevimab]] for post-exposure prophylaxis against [[COVID-19]].<ref>{{cite web |last1=Research |first1=Center for Drug Evaluation and |title=FDA authorizes bamlanivimab and etesevimab monoclonal antibody therapy for post-exposure prophylaxis (prevention) for COVID-19 |url=https://www.fda.gov/drugs/drug-safety-and-availability/fda-authorizes-bamlanivimab-and-etesevimab-monoclonal-antibody-therapy-post-exposure-prophylaxis |website=FDA |language=en |date=16 September 2021 |access-date=24 April 2022 |archive-date=17 September 2021 |archive-url=https://web.archive.org/web/20210917083810/https://www.fda.gov/drugs/drug-safety-and-availability/fda-authorizes-bamlanivimab-and-etesevimab-monoclonal-antibody-therapy-post-exposure-prophylaxis |url-status=dead }}</ref> However, due to its reduced effectiveness against [[SARS-CoV-2 Omicron variant|Omicron variant]]s of the SARS-CoV-2 virus, it is no longer recommended for this purpose.<ref name="NIH 2023">{{cite web |title=Prevention of SARS-CoV-2 |website=NIH |date=20 December 2023 |url=https://www.covid19treatmentguidelines.nih.gov/overview/prevention-of-sars-cov-2/ |access-date=27 January 2024}}</ref>

[[Ensitrelvir]] has been studied for its potential use as post-exposure prophylaxis against COVID-19 in a phase 3 clinical trial.<ref>{{cite web |last=Cosdon |first=Nina |title=Ensitrelvir: A COVID-19 Antiviral That Remains Effective Against New Variants |website=ContagionLive |date=31 March 2023 |url=https://www.contagionlive.com/view/ensitrelvir-a-covid-19-antiviral-that-remains-effective-against-new-variants |access-date=28 October 2023 |archive-date=31 October 2023 |archive-url=https://web.archive.org/web/20231031071100/https://www.contagionlive.com/view/ensitrelvir-a-covid-19-antiviral-that-remains-effective-against-new-variants |url-status=live }}</ref><ref >{{cite web |title=Shionogi presses on with Xocova research following Japanese approval |website=[[The Pharma Letter]] |date=16 February 2023 |url=https://www.thepharmaletter.com/article/shionogi-presses-on-with-xocova-research-following-japanese-approval |access-date=28 October 2023 |archive-date=28 October 2023 |archive-url=https://web.archive.org/web/20231028053044/https://www.thepharmaletter.com/article/shionogi-presses-on-with-xocova-research-following-japanese-approval |url-status=live }}</ref><ref>{{cite web |title=Studies Currently Enrolling |website=University of Kansas Medical Center |url=https://www.kumc.edu/school-of-medicine/campuses/wichita/research/center-for-clinical-research-wichita/clinical-trials/studies-currently-enrolling.html |access-date=28 October 2023 |archive-url=https://web.archive.org/web/20231028051723/https://www.kumc.edu/school-of-medicine/campuses/wichita/research/center-for-clinical-research-wichita/clinical-trials/studies-currently-enrolling.html |archive-date=28 October 2023 |quote=SCORPIO-PEP is a 28-day study to assess the prevention of COVID-19 infection in those who have been exposed through household contact.}}</ref> Top-line results from this trial suggested that use of ensitrelvir as post-exposure prophylaxis may significantly reduce the risk of symptomatic COVID-19 infection in exposed household contacts compared to placebo.<ref name="Ernst 2024">{{cite web |vauthors=Ernst D |title=Ensitrelvir Looks Promising for COVID-19 Postexposure Prophylaxis |website=MPR |date=8 November 2024 |url=https://www.empr.com/news/ensitrelvir-looks-promising-for-covid-19-postexposure-prophylaxis/ |access-date=25 January 2025}}</ref><ref name="ContagionLive 2024">{{cite web |title=Antiviral Prevents Symptomatic COVID-19 in Post-Exposure Prophylactic Study |website=ContagionLive |date=29 October 2024 |url=https://www.contagionlive.com/view/antiviral-prevents-symptomatic-covid-19-in-post-exposure-prophylactic-study |access-date=25 January 2025}}</ref><ref name="Swift 2024">{{cite web |vauthors=Swift R |title=Japan's Shionogi says Phase 3 study showed COVID pill reduces transmission |website=Reuters |date=29 October 2024 |url=https://www.reuters.com/business/healthcare-pharmaceuticals/japans-shionogi-says-phase-3-study-showed-covid-pill-reduces-transmission-2024-10-29/ |access-date=25 January 2025}}</ref>

== Rabies ==
PEP is commonly and very effectively used to prevent the onset of [[rabies]] after a bite by a suspected-rabid animal, since diagnostic tools are not available to detect rabies infection prior to the onset of the nearly always-fatal disease.<ref>{{cite web |url=https://www.who.int/news-room/fact-sheets/detail/rabies |title=Rabies |publisher=[[World Health Organization]] |website=www.who.int |access-date=2019-06-16 |archive-date=2019-05-09 |archive-url=https://web.archive.org/web/20190509201021/https://www.who.int/news-room/fact-sheets/detail/rabies |url-status=live }}</ref> The treatment consists of a series of injections of [[rabies vaccine]] and [[immunoglobulin]].<ref name="titleWHO |Guide for post-exposure prophylaxis">{{cite web |url=https://www.who.int/rabies/human/postexp/en/index.html |archive-url=https://web.archive.org/web/20040627051139/http://www.who.int/rabies/human/postexp/en/index.html |url-status=dead |archive-date=June 27, 2004 |title=Rabies: Guide for post-exposure prophylaxis|publisher=[[World Health Organization]]|access-date=2013-05-28 }}</ref> [[Rabies vaccine]] is given to both humans and animals who have been potentially exposed to [[rabies]].<ref name="Wiktor_1984">{{cite journal|vauthors=Wiktor TJ, Macfarlan RI, Reagan KJ, Dietzschold B, Curtis PJ, Wunner WH, Kieny MP, Lathe R, Lecocq JP, Mackett M |title=Protection from rabies by a vaccinia virus recombinant containing the rabies virus glycoprotein gene|journal=Proc. Natl. Acad. Sci. U.S.A.|volume=81|issue=22 |pages=7194–8 |year=1984 |pmid=6095272 | doi = 10.1073/pnas.81.22.7194 |pmc=392104|bibcode=1984PNAS...81.7194W|doi-access=free}}</ref>

As of 2018, the average estimated cost of rabies post-exposure prophylaxis was US$ 108 (along with travel costs and loss of income).<ref>{{Cite web |title=Rabies |url=https://www.who.int/news-room/fact-sheets/detail/rabies |access-date=2024-08-13 |website=www.who.int |language=en}}</ref>

== Tetanus ==
[[Tetanus]] toxoid can be given in case of a suspected exposure to tetanus. In such cases, it can be given with or without tetanus [[immunoglobulin]] (also called ''tetanus antibodies'' or ''tetanus antitoxin''<ref name="britannica2013">{{Cite web |title=Tetanus antitoxin {{!}} biochemistry {{!}} Britannica |url=https://www.britannica.com/science/tetanus-antitoxin |access-date=2023-11-08 |website=www.britannica.com |language=en}}</ref>). It can be given as [[intravenous therapy]] or by [[intramuscular injection]].{{citation needed|date=April 2021}}

The guidelines for such events in the United States for non-pregnant people 11 years and older are as follows:<ref>[https://www.cdc.gov/vaccines/pubs/pinkbook/downloads/tetanus.pdf "Tetanus"] {{Webarchive|url=https://web.archive.org/web/20080306134607/http://www.cdc.gov/vaccines/pubs/pinkbook/downloads/tetanus.pdf |date=2008-03-06 }}, from the [[Centers for Disease Control and Prevention]]. Page last updated August 12, 2013.</ref>

{|class="wikitable"
!Vaccination status !! Clean, minor wounds !! All other wounds
|-
|Unknown or fewer than three doses of tetanus toxoid containing vaccine || [[Tdap]] and recommend catch-up vaccination || [[Tdap]] and recommend catch-up vaccination<br /> Tetanus [[immunoglobulin]]
|-
|Three or more doses of tetanus toxoid containing vaccine AND less than 5 years since last dose
|No indication || No indication
|-
|Three or more doses of tetanus toxoid containing vaccine AND 5–10 years since last dose
|No indication || Tdap preferred (if not yet received) or Td
|-
|Three or more doses of tetanus toxoid containing vaccine AND more than 10 years since last dose
|Tdap preferred (if not yet received) or Td || Tdap preferred (if not yet received) or Td
|}

== HIV ==
[[File:PEPMeds2023.jpg|thumb|HIV post exposure prophylaxis medication used in Canada in 2023 include a combination of [[lamivudine]], [[tenofovir]], and [[raltegravir]]]]

=== History ===
[[Zidovudine|AZT]] was approved as a treatment for [[AIDS]] in 1987. Healthcare workers would occasionally be exposed to [[HIV]] during work.  Some people{{who|date=November 2017}} thought to try giving health care workers AZT to prevent [[seroconversion]].  This practice dramatically decreased the incidence of seroconversion among health workers when done under certain conditions.<ref name="healthcareworkers">{{Cite journal | last1 = Cardo | first1 = D. M. | last2 = Culver | first2 = D. H. | last3 = Ciesielski | first3 = C. A. | last4 = Srivastava | first4 = P. U. | last5 = Marcus | first5 = R. | last6 = Abiteboul | first6 = D. | last7 = Heptonstall | first7 = J. | last8 = Ippolito | first8 = G. | last9 = Lot | first9 = F. | last10 = McKibben | doi = 10.1056/NEJM199711203372101 | first10 = P. S. | last11 = Bell | first11 = D. M. | title = A Case–Control Study of HIV Seroconversion in Health Care Workers after Percutaneous Exposure | journal = New England Journal of Medicine | volume = 337 | issue = 21 | pages = 1485–1490 | year = 1997 | pmid = 9366579 | doi-access = free }}</ref>

Later the questions arose of whether to give HIV treatment after known exposure or high risk of exposure. Early data from [[Preclinical development|preclinical studies]] established the efficacy of AZT in preventing transmission of HIV infection.<ref>{{cite journal|last1=Shih|first1=CC|last2=Kaneshima|first2=H|last3=Rabin|first3=L|last4=Namikawa|first4=R|last5=Sager|first5=P|last6=McGowan|first6=J|last7=McCune|first7=JM|title=Postexposure prophylaxis with zidovudine suppresses human immunodeficiency virus type 1 infection in SCID-hu mice in a time-dependent manner.|journal=The Journal of Infectious Diseases|date=March 1991|volume=163|issue=3|pages=625–7|pmid=1995734|doi=10.1093/infdis/163.3.625}}</ref> AZT was also seen to reduce maternal-infant transmission of HIV in a [[randomized controlled trial]], suggesting AZT's post-exposure prophylaxis (PEP) use.<ref>{{cite journal|last1=Connor|first1=EM|last2=Sperling|first2=RS|last3=Gelber|first3=R|last4=Kiselev|first4=P|last5=Scott|first5=G|last6=O'Sullivan|first6=MJ|last7=VanDyke|first7=R|last8=Bey|first8=M|last9=Shearer|first9=W|last10=Jacobson|first10=RL|title=Reduction of maternal-infant transmission of human immunodeficiency virus type 1 with zidovudine treatment. Pediatric AIDS Clinical Trials Group Protocol 076 Study Group.|journal=The New England Journal of Medicine|date=3 November 1994|volume=331|issue=18|pages=1173–80|doi=10.1056/NEJM199411033311801|pmid=7935654|s2cid=13457499|doi-access=free}}</ref> Subsequent data show [[Management of HIV/AIDS|combination antiretroviral therapy]] is significantly superior than AZT in reducing perinatal transmission rates.<ref>{{cite journal|last1=Watts|first1=DH|title=Management of human immunodeficiency virus infection in pregnancy.|journal=The New England Journal of Medicine|date=13 June 2002|volume=346|issue=24|pages=1879–91|doi=10.1056/NEJMra013338|pmid=12063373}}</ref> In addition, AZT is generally no longer recommended due to poor tolerance resulting in high rates of patient noncompliance.{{citation needed|date=January 2021}}

Non-occupational exposures include cases when a condom breaks while a person with HIV has sex with an HIV-negative person in a single incidence, or in the case of unprotected sex with an anonymous partner, or in the case of a non-habitual incident of sharing a syringe for [[Drug injection|injection drug use]].  Evidence suggests that PEP also reduces the risk of HIV infection in these cases.<ref>{{Cite journal | last1 = Katz | first1 = M. H. | last2 = Gerberding | first2 = J. L. | doi = 10.1056/NEJM199704103361512 | title = Postexposure Treatment of People Exposed to the Human Immunodeficiency Virus through Sexual Contact or Injection-Drug Use | journal = New England Journal of Medicine | volume = 336 | issue = 15 | pages = 1097–1100 | year = 1997 | pmid =  9091810}}</ref> In 2005, the [[United States Department of Health and Human Services|US DHHS]] released the first recommendations for non-occupational PEP (nPEP) use to lower risk of HIV infection after exposures. The recommendations were replaced with an updated guideline in 2016.<ref name=":0">{{cite web | url=https://www.cdc.gov/hiv/pdf/programresources/cdc-hiv-npep-guidelines.pdf | title=Updated Guidelines for Antiretroviral Postexposure Prophylaxis After Sexual, Injection Drug Use, or Other Nonoccupational Exposure to HIV— United States, 2016 | publisher=Centers for Disease Control and Prevention, U.S. Department of Health and Human Services | access-date=June 24, 2016 | archive-date=November 20, 2016 | archive-url=https://web.archive.org/web/20161120134302/http://www.cdc.gov/hiv/pdf/programresources/cdc-hiv-npep-guidelines.pdf | url-status=live }}</ref>

Occupational exposures include needlestick injury of health care professionals from an HIV-infected source. In 2012, the [[United States Department of Health and Human Services|US DHHS]] included guidelines on occupational PEP (oPEP) use for individuals with HIV exposures occurring in health care settings.<ref>{{cite journal|last1=Kuhar|first1=David T.|last2=Henderson|first2=David K.|last3=Struble|first3=Kimberly A.|last4=Heneine|first4=Walid|last5=Thomas|first5=Vasavi|last6=Cheever|first6=Laura W.|last7=Gomaa|first7=Ahmed|last8=Panlilio|first8=Adelisa L.|title=Updated US Public Health Service guidelines for the management of occupational exposures to human immunodeficiency virus and recommendations for postexposure prophylaxis|journal=Infection Control and Hospital Epidemiology|pages=875–892|doi=10.1086/672271|date=2013|pmid=23917901|volume=34|issue=9|s2cid=17032413|url=https://zenodo.org/record/1235708|access-date=2018-11-04|archive-date=2019-06-23|archive-url=https://web.archive.org/web/20190623220711/https://zenodo.org/record/1235708|url-status=live}}</ref>

Since taking HIV-attacking medications shortly after exposure was proven to reduce the risk of contracting HIV, this led to research into [[pre-exposure prophylaxis]] by taking medication before a potential exposure to HIV occurred.<ref>{{cite journal | last1=Desai | first1=Monica | last2=Field | first2=Nigel | last3=Grant | first3=Robert | last4=McCormack | first4=Sheena | title=State of the art review: Recent advances in PrEP for HIV | journal=BMJ (Clinical Research Ed.) | volume=359 | date=2017-12-11 | pages=j5011 | pmid=29229609 | doi=10.1136/bmj.j5011 | pmc=6020995 }}</ref>

A report from early 2013 revealed that a female baby born with the HIV virus displayed no sign of the virus two years after high doses of three antiretroviral drugs were administered within 30 hours of her birth. The findings of the case were presented at the 2013 Conference on Retroviruses and Opportunistic Infections in [[Atlanta]], U.S. and the baby is from [[Mississippi]], U.S. The baby—known as the "[[Mississippi baby]]"—was considered to be the first child to be "functionally cured" of HIV.<ref>{{cite news|url=https://edition.cnn.com/2013/03/03/health/hiv-toddler-cured|title=Researchers: Toddler cured of HIV|author=Saundra Young|date=4 March 2013|newspaper=CNN|access-date=4 July 2013|archive-date=19 May 2013|archive-url=https://web.archive.org/web/20130519070343/http://edition.cnn.com/2013/03/03/health/hiv-toddler-cured|url-status=live}}</ref> However, HIV re-emerged in the child as of July 2014.<ref>{{cite news|url=https://www.niaid.nih.gov/news/newsreleases/2014/Pages/MississippiBabyHIV.aspx|title="Mississippi Baby" Now Has Detectable HIV, Researchers Find|author=National Institute of Allergy and Infectious Diseases|date=10 July 2014|newspaper=NIH|access-date=12 August 2014|archive-date=9 September 2016|archive-url=https://web.archive.org/web/20160909164118/http://www.niaid.nih.gov/news/newsreleases/2014/Pages/MississippiBabyHIV.aspx|url-status=live}}</ref>

=== Risk evaluation ===
Initiation of post-exposure prophylaxis with the use of [[antiretroviral]] drugs is dependent on a number of [[risk factors]], though treatment is usually started after one high-risk event. In order to determine whether post-exposure prophylaxis is indicated, an evaluation visit will be conducted to consider risk factors associated with developing [[HIV]]. Assessments at this visit will include whether the at-risk person or the potential source-person are [[HIV positive]], details around the potential HIV exposure event, including timing and circumstances, whether other high-risk events have occurred in the past, testing for [[sexually transmitted diseases]], testing for [[hepatitis B]] and [[Hepatitis C|C]] (nPEP is also effective against [[hepatitis B]]), and pregnancy tests for women of childbearing potential.<ref name=":0" />

Risk factors for developing HIV includes exposure of [[mucous membranes]] (vagina, rectum, eye, mouth, broken skin or under the skin) of an HIV-negative person to [[bodily fluids]] (blood, semen, rectal secretions, vaginal secretions, breast milk) of a person known to be [[HIV positive]]. For example, having [[unprotected sex]] with [[HIV positive]] partner is considered risky, but sharing sex toys, spitting and biting considered to be negligible risks for initiating post-exposure prophylaxis. The highest non-sexual risk is [[blood transfusion]] and the highest sexual contact risk is receptive anal intercourse. The timing of exposure does not affect the risk of developing HIV, but it does alter whether post-exposure prophylaxis will be recommended. Exposures that occurred 72 hours or less to beginning treatment are eligible for post-exposure prophylaxis. If the exposure occurred over 73 hours prior to treatment initiation, post-exposure prophylaxis is not indicated.<ref name=":0" />

=== Testing ===
'''Initial HIV testing:''' Before initiating PEP after potential [[HIV]] exposure, persons should be tested for [[HIV1]] and [[HIV2]] antigens and antibodies in the blood using a [[rapid diagnostic test]]. PEP should only be started if rapid diagnostic test reveals no HIV infection present or if tests results are not available.  However, if HIV infection is already present then PEP should not be started. HIV testing should be repeated four to six weeks and three months after exposure.<ref name=":0" />

People may experience signs and symptoms of [[acute HIV infection]], including fever, fatigue, myalgia, and skin rash, while taking PEP. CDC recommends seeking medical attention for evaluation if these signs and symptoms occur during or after the month of PEP.  If follow-up laboratory antibody tests reveal HIV infection, HIV treatment specialists should be sought out and PEP should not be discontinued until person is evaluated and treatment plan is established.<ref name=":0" />

'''STI and HBV testing:''' People with potential exposure to HIV are also at risk of acquiring [[Sexually transmitted infection|STI]] and [[Hepatitis B virus|HBV]]. [[Centers for Disease Control and Prevention]] (CDC) recommends STI-specific nucleic acid amplification testing ([[NAAT]]) for [[gonorrhea]] and [[chlamydia]] and blood tests for [[syphilis]]. PEP is also active against HBV infections so discontinuation of medication can cause the reactivation of [[Hepatitis B virus|HBV]], though rare. Health care providers must monitor HBV status closely.<ref name=":0" />

'''Follow up testing:''' [[Serum creatinine]] and estimated [[creatinine clearance]] should be measured at baseline to determine the most appropriate PEP antiretroviral regimen. While on PEP, [[liver function tests|liver function]], [[renal function]], and hematologic parameters should be monitored.<ref name=":0" />

=== Treatment ===
In the case of [[HIV]] exposure, post-exposure prophylaxis (PEP) is a course of [[antiretroviral]] drugs which reduces the risk of [[seroconversion]] after events with high risk of exposure to HIV (e.g., unprotected [[anal sex|anal]] or [[vaginal sex]], [[needlestick injuries]], or [[needle sharing|sharing needles]]).<ref name="CDC">{{cite web |url=https://www.cdc.gov/mmwr/preview/mmwrhtml/rr5402a1.htm |title=Antiretroviral Postexposure Prophylaxis After Sexual, Injection-Drug Use, or Other Nonoccupational Exposure to HIV in the United States |last1=Smith |first1=Dawn K. |last2=Grohskopf |first2=Lisa A. |last3=Black |first3=Roberta J. |last4=Auerbach |first4=Judith D. |last5=Veronese |first5=Fulvia |last6=Struble |first6=Kimberly A. |date=21 January 2005 |work=cdc.gov |publisher=[[Centers for Disease Control]] |access-date=7 July 2011 |archive-date=14 April 2011 |archive-url=https://web.archive.org/web/20110414180947/http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5402a1.htm |url-status=live }}</ref> The [[Centers for Disease Control|CDC]] recommends PEP for any HIV-negative person who has recently been exposed to HIV for any reason.<ref name="CDC"/>

To be most effective, treatment should begin within an hour of exposure.<ref name="ignorance">{{cite journal |last1=Diprose |first1=P |last2=Deakin |first2=C.D. |last3=Smedley |first3=J |year=2000 |title=Ignorance of post-exposure prophylaxis guidelines following HIV needlestick injury may increase the risk of seroconversion |journal=[[British Journal of Anaesthesia]] |volume=84 |issue=6 |pages=767–770 |doi= 10.1093/oxfordjournals.bja.a013591|pmid=10895754|doi-access=free }}</ref> After 72 hours PEP is much less effective, and may not be effective at all.<ref name="CDC"/> Prophylactic treatment for HIV typically lasts four weeks.<ref name="CDC"/><ref>{{cite web |url=http://hab.hrsa.gov/tools/HIVpocketguide/PktGPEP.htm |title=HIV/AIDS Bureau - HIV Care Pocket Guide 2006 - Occupational HIV Postexposure Prophylaxis (PEP) |access-date=2008-03-05 |url-status=dead |archive-url=https://web.archive.org/web/20080311174937/http://hab.hrsa.gov/tools/HIVpocketguide/PktGPEP.htm |archive-date=2008-03-11 }}</ref>

While there is compelling data to suggest that PEP after HIV exposure is effective, there have been cases where it has failed. Failure has often been attributed to the delay in receiving treatment (greater than 72 hours post-exposure), the level of exposure, and/or the duration of treatment (lack of adherence to the 28-day regimen). In addition, since the time and level of non-occupational exposures are self-reported, there is no absolute data on the administration timeframe to which PEP would be efficacious. The standard antibody window period begins after the last day of PEP treatment. People who received PEP are typically advised to get an antibody test at 6 months post-exposure as well as the standard 3 month test.<ref name="CDC"/>

The antiretroviral regimen used in PEP is the same as the standard [[highly active antiretroviral therapy]] used to treat AIDS. A typical prescription is a 28-day course of [[emtricitabine/tenofovir]] pills containing 200&nbsp;mg of emtricitabine and 245&nbsp;mg of tenofovir disoproxil to be taken once daily, along with either 50&nbsp;mg of [[dolutegravir]] once daily<ref name=":0" /> or 400&nbsp;mg of [[raltegravir]] twice daily.<ref>{{Cite web |url=https://www.uhb.nhs.uk/Downloads/pdf/PiPepMedication28Day.pdf |title=Archived copy |access-date=2021-06-07 |archive-date=2021-06-07 |archive-url=https://web.archive.org/web/20210607084606/https://www.uhb.nhs.uk/Downloads/pdf/PiPepMedication28Day.pdf |url-status=dead }}</ref> People initiating nPEP treatment typically receive a 28-day starter pack rather than a 3–7 day starter pack, to facilitate strong [[medication adherence]].<ref name=":0" /> They should also be counseled on unpleasant side effects including [[malaise]], [[fatigue (physical)|fatigue]], [[diarrhea]], [[headache]], [[nausea]], [[vomiting]], and [[insomnia]], depending on the medication administered.<ref name="CDC"/><ref>{{Cite web |title=Dolutegravir Sodium Monograph for Professionals |url=https://www.drugs.com/monograph/dolutegravir-sodium.html |access-date=2025-01-24 |website=Drugs.com |language=en}}</ref>

People at high risk for re-exposure due to unprotected intercourse or other behavioral factors should begin [[Pre-exposure prophylaxis|PrEP]] immediately after the completion of the nPEP treatment course. Conversely, if a medically adherent patient is already taking PrEP medication upon non-occupational exposure, nPEP treatment is not necessary.<ref name=":0" />

== Hepatitis A ==
For exposure to [[hepatitis A]], human normal [[immunoglobulin]] (HNIG) and/or [[hepatitis A vaccine]] may be used as PEP depending on the clinical situation.<ref>{{cite web | title=Hepatitis A Questions and Answers for Health Professionals | website=CDC | date=November 9, 2018 | url=https://www.cdc.gov/hepatitis/hav/havfaq.htm | access-date=December 9, 2018 | archive-date=March 6, 2016 | archive-url=https://web.archive.org/web/20160306221037/http://www.cdc.gov/hepatitis/hav/havfaq.htm | url-status=live }}</ref><ref>{{cite journal | author=CDC | title=Updated Dosing Instructions for Immune Globulin (Human) GamaSTAN S/D for Hepatitis A Virus Prophylaxis| journal=MMWR. Morbidity and Mortality Weekly Report | volume=66 | issue=36| pages=959–960| date=September 14, 2017 | issn=0149-2195|eissn= 1545-861X| doi=10.15585/mmwr.mm6636a5 | pmid=28910270| pmc=5657912}}</ref>

== Hepatitis B ==
If the person exposed is an [[HBsAg]] positive source (a known responder to [[hepatitis B vaccine|HBV vaccine]]) then if exposed to [[hepatitis B]] a booster dose should be given. If they are in the process of being vaccinated or are a non-responder they need to have [[hepatitis B immune globulin]] (HBIG) and the vaccine. For known non-responders HBIG and the vaccine should be given whilst those in the process of being vaccinated should have an accelerated course of HBV vaccine.{{citation needed|date=July 2011}}<ref>{{Cite web |last= |first= |title=Post-exposure Prophylaxis Hepatitis B |url=http://conditions.health.qld.gov.au/HealthCondition/condition/14/188/114/post-exposure-prophylaxis-hepatitis-b |access-date=2022-05-25 |website=conditions.health.qld.gov.au |language=en |archive-date=2022-03-04 |archive-url=https://web.archive.org/web/20220304213919/http://conditions.health.qld.gov.au/HealthCondition/condition/14/188/114/Post-exposure-Prophylaxis-Hepatitis-B |url-status=live }}</ref>

== Hepatitis C ==
{{Update|part=section|date=April 2023|reason=new generation antiviral drugs for Hepatitis C negate the need for Interferon and Ribavirin}}
Persons exposed to [[hepatitis C]] should be tested monthly with [[Polymerase chain reaction|PCR]], and if [[seroconversion]] occurs then treatment with [[interferon]], or possibly [[ribavirin]].{{Citation needed|date=July 2011}}

== Anthrax ==
A 60-day course of oral [[ciprofloxacin]] should be given when exposure to [[anthrax]] is suspected.<ref>{{cite web|url=https://www.cdc.gov/anthrax/medical-care/prevention.html|title=Prevention - Anthrax - CDC|date=9 January 2019|website=www.cdc.gov|access-date=9 December 2018|archive-date=10 December 2018|archive-url=https://web.archive.org/web/20181210063228/https://www.cdc.gov/anthrax/medical-care/prevention.html|url-status=live}}</ref>

== Lyme disease ==
A single 200 milligram oral dose of [[doxycycline]] may be used within 3 days of a [[Ixodes scapularis|deer tick]] bite in a high risk area (such as [[New England]]), if the tick was attached for at least 36 hours.<ref>{{cite web |title=Tick Bite Prophylaxis |url=https://www.cdc.gov/ticks/tickbornediseases/tick-bite-prophylaxis.html |website=Centers for Disease Control and Prevention |access-date=20 May 2021 |language=en-us |date=30 May 2019 |archive-date=26 May 2021 |archive-url=https://web.archive.org/web/20210526173741/https://www.cdc.gov/ticks/tickbornediseases/tick-bite-prophylaxis.html |url-status=live}}</ref><ref name="pmid34749665">{{cite journal |vauthors=Zhou G, Xu X, Zhang Y, Yue P, Luo S, Fan Y, Chen J, Liu M, Dong Y, Li B, Kong J, Wen S, Liu A, Bao F |title=Antibiotic prophylaxis for prevention against Lyme disease following tick bite: an updated systematic review and meta-analysis |journal=BMC Infectious Diseases |volume=21 |issue=1 |pages=1141 |date=November 2021 |pmid=34749665 |pmc=8573889 |doi=10.1186/s12879-021-06837-7|doi-access=free }}</ref><ref name="pmid33251700">{{cite journal |vauthors=Lantos PM, Rumbaugh J, Bockenstedt LK, Falck-Ytter YT, Aguero-Rosenfeld ME, Auwaerter PG, Baldwin K, Bannuru RR, Belani KK, Bowie WR, Branda JA, Clifford DB, DiMario FJ, Halperin JJ, Krause PJ, Lavergne V, Liang MH, Cody Meissner H, Nigrovic LE, Nocton JJ, Osani MC, Pruitt AA, Rips J, Rosenfeld LE, Savoy ML, Sood SK, Steere AC, Strle F, Sundel R, Tsao J, Vaysbrot EE, Wormser GP, Zemel LS |title=Clinical Practice Guidelines by the Infectious Diseases Society of America (IDSA), American Academy of Neurology (AAN), and American College of Rheumatology (ACR): 2020 Guidelines for the Prevention, Diagnosis, and Treatment of Lyme Disease |journal=Arthritis Care & Research |volume=73 |issue=1 |pages=1–9 |date=January 2021 |pmid=33251700 |doi=10.1002/acr.24495 |quote=We recommend that prophylactic antibiotic therapy be given only to adults and children within 72 hours of removal of an identified high-risk tick bite, but not for bites that are equivocal risk or low risk (strong recommendation, high-quality evidence). comment: If a tick bite cannot be classified with a high level of certainty as a high-risk bite, a wait-and-watch approach is recommended. A tick bite is considered to be high-risk only if it meets the following three criteria: the tick bite was from (a) an identified Ixodes spp. vector species, (b) it occurred in a highly endemic area, and (c) the tick was attached for ≥36 hour|doi-access=free }}</ref>

== Poxviruses ==
The smallpox vaccine decreases the incidence risk of severe illness when administered after exposure to [[mpox]] and [[smallpox]]. The CDC advises "that smallpox vaccine be given within 4 days from the date of exposure to prevent onset of the disease but should be offered up to 14 days post-exposure"; the NHS concurs with this but also urges to vaccinate as soon as possible after exposure.<ref>{{cite web |url=https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1083791/Recommendations-for-pre-and-post-exposure-vaccination-during-a-monkeypox-incident-17-june-2022.pdf |title=Recommendations for the use of pre and post exposure vaccination during a monkeypox incident |date=17 June 2022 |access-date=9 July 2022 |website=assets.publishing.service.gov.uk |quote=Vaccination should be administered as soon as possible and within 4 days after an identified exposure to prevent or attenuate infection. |archive-date=3 July 2022 |archive-url=https://web.archive.org/web/20220703113647/https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1083791/Recommendations-for-pre-and-post-exposure-vaccination-during-a-monkeypox-incident-17-june-2022.pdf |url-status=live }}</ref>

== See also ==
* [[Pre-exposure prophylaxis]] (PrEP)

== References ==
{{reflist|30em}}

== Further reading ==
* {{cite journal|last=Landovitz|first=RJ|author2=Currier, JS|title=Clinical practice. Postexposure prophylaxis for HIV infection|journal=The New England Journal of Medicine|date=Oct 29, 2009|volume=361|issue=18|pages=1768–75|doi=10.1056/NEJMcp0904189|pmid=19864675|doi-access=free}}
* {{cite journal|last=Landovitz|first=RJ|title=Occupational and nonoccupational postexposure prophylaxis for HIV in 2009.|journal=Topics in HIV Medicine |date=Jul–Aug 2009|volume=17|issue=3|pages=104–8|pmid=19675368}}
* {{cite journal|last=Havens|first=PL|author2=American Academy of Pediatrics Committee on Pediatric, AIDS|title=Postexposure prophylaxis in children and adolescents for nonoccupational exposure to human immunodeficiency virus.|journal=Pediatrics|date=Jun 2003|volume=111|issue=6 Pt 1|pages=1475–89|pmid=12777574|doi=10.1542/peds.111.6.1475|doi-access=free}}
* {{cite journal|last=Jost|first=J|title=[Post-exposure HIV prevention within and outside the hospital].|journal=Therapeutische Umschau. Revue therapeutique|date=May 1998|volume=55|issue=5|pages=289–94|pmid=9643126|language=de}}

== External links ==
* [https://www.cdc.gov/mmwr/preview/mmwrhtml/rr5402a1.htm CDC on nonoccupational HIV postexposure prophylaxis], an article which summarizes more than 100 related research projects
* [https://web.archive.org/web/20030108211625/http://www.who.int/hiv/topics/prophylaxis/en/ HIV/AIDS Post-exposure prophylaxis]: WHO
* [http://www.aids-ed.org/aidsetc?page=cg-301_occupational_pep Occupational Postexposure Prophylaxis] {{Webarchive|url=https://web.archive.org/web/20140202092848/http://www.aids-ed.org/aidsetc?page=cg-301_occupational_pep |date=2014-02-02 }}: HRSA HIV/AIDS Bureau, The AIDS Education and Training Centers (AETC)

{{Concepts in infectious disease}}
{{DEFAULTSORT:Post-Exposure Prophylaxis}}
[[Category:Medical treatments]]
[[Category:Prevention of HIV/AIDS]]