Prevention tool
DoxyPEP Eligibility Checker: Do You Qualify for Doxy-PEP?
Doxy-PEP is a single antibiotic dose taken after sex to prevent chlamydia, gonorrhea and syphilis. Answer two quick questions, anonymously, in your browser, to see whether you match the CDC's 2024 criteria, then take the result to a provider.
Doxy-PEP eligibility checker
This is general information from the CDC guidelines, not a prescription, diagnosis, or medical advice. Doxy-PEP is prescription-only, only a clinician can decide if it's right for you.
The basics
What is doxy-PEP?
Doxy-PEP (doxycycline post-exposure prophylaxis) is a single 200 mg dose of the antibiotic doxycycline, taken after condomless sex to lower the chance of catching three bacterial STIs: chlamydia, gonorrhea, and syphilis. It is "post-exposure," meaning it's taken around the time of a possible exposure, not every day like HIV PrEP.
In three large randomized trials, 200 mg taken within 72 hours of sex reduced syphilis and chlamydia by more than 70% and gonorrhea by about 50%. Gonorrhea protection is lower and depends on local antibiotic resistance, which is one reason it's offered as part of ongoing testing, not on its own.
CDC 2024 guidance
Who is doxy-PEP recommended for?
The CDC's 2024 clinical guidelines recommend that providers counsel and, through shared decision-making, offer doxy-PEP to:
Recommended
Gay and bisexual men and other men who have sex with men, and transgender women, who have had chlamydia, gonorrhea, or syphilis in the past 12 months.
Insufficient evidence
Cisgender women, cisgender heterosexual men, and transgender men: a trial in cisgender women did not show benefit, so the CDC does not routinely recommend it. Ask your provider about other prevention.
A recent bacterial STI is the CDC's threshold because it identifies people at higher ongoing risk. A provider may still consider doxy-PEP for others in the recommended groups at substantial risk, again through shared decision-making.
Using it safely
How to take doxy-PEP, and what it can't do
200 mg, once
A single 200 mg dose of doxycycline per exposure.
Within 72 hours
As soon as possible after sex: ideally under 72h, not before.
Max once / 24h
No more than 200 mg in any 24-hour period.
Doxy-PEP is not a cure and not a stand-alone shield. It only lowers the risk of three bacterial STIs: it does not prevent HIV, herpes, HPV, hepatitis, trichomoniasis, or mpox. The CDC frames it as one part of a fuller plan: condoms, HIV PrEP, vaccination, and STI testing every 3–6 months.
Because it uses an antibiotic, doxy-PEP is monitored for effects on antimicrobial resistance and the body's normal bacteria, which is another reason it's prescribed and followed by a clinician rather than self-started.
Next steps
Where to get doxy-PEP
Doxy-PEP is prescription-only. A primary-care provider, sexual-health or STI clinic, HIV/PrEP clinic, or telehealth sexual-health service can assess you and prescribe it. Bring your result from the checker to that conversation.
Sources
Where this guidance comes from
Every recommendation on this page is drawn from the U.S. Centers for Disease Control and Prevention's official 2024 clinical guidelines for doxy-PEP. We do not add to or reinterpret them.
Medically Reviewed & Fact-Checked · Updated
Reviewed by EasySTD Editorial Team
Compiled and checked by EasySTD's editorial team against CDC and public-health sources. This is educational information, not a substitute for advice from a licensed clinician. Our editorial guidelines →
2 Sources
Data & references
- CDC: Clinical Guidelines on Doxycycline Postexposure Prophylaxis (MMWR, 2024)https://www.cdc.gov/mmwr/volumes/73/rr/rr7302a1.htm
- CDC: Sexually Transmitted Infectionshttps://www.cdc.gov/sti/
EasySTD is an information and comparison directory, not a healthcare provider. This checker is general information based on published CDC guidelines: it is not medical advice, a diagnosis, or a prescription, and it does not create a doctor-patient relationship. Always consult a qualified clinician.
Good to Know
Doxy-PEP: frequently asked questions
The essentials on eligibility, dosing, and access.
Who is eligible for doxy-PEP?
The CDC's 2024 guidelines recommend counseling on doxy-PEP for gay and bisexual men and other men who have sex with men (MSM) and for transgender women who have had a bacterial STI, chlamydia, gonorrhea, or syphilis, diagnosed in the past 12 months. For these groups, providers should offer a prescription through shared decision-making.
Can cisgender women or heterosexual men take doxy-PEP?
Not as a routine recommendation. The CDC found insufficient evidence of benefit for cisgender women, cisgender heterosexual men, and transgender men, a key trial in cisgender women did not show a protective effect. If you're in one of these groups, talk to your provider about other prevention: condoms, vaccination (HPV, hepatitis, mpox), regular testing, and HIV PrEP.
How and when do I take doxy-PEP?
The regimen is a single 200 mg dose of doxycycline taken as soon as possible, and ideally within 72 hours, after oral, vaginal, or anal sex, not to exceed 200 mg in any 24-hour period. It is taken after sex (post-exposure), not daily.
How well does doxy-PEP work?
In three large randomized trials, 200 mg of doxycycline within 72 hours of sex reduced syphilis and chlamydia infections by more than 70% and gonorrhea by roughly 50%. Gonorrhea protection is lower and varies with local antibiotic resistance.
Does doxy-PEP replace condoms, vaccines, or HIV PrEP?
No. Doxy-PEP only lowers the risk of three bacterial STIs. It does not prevent HIV or other infections, and it is meant to sit alongside condoms, vaccination, HIV PrEP, and routine STI testing every 3–6 months, not replace them.
Where do I get doxy-PEP?
Doxy-PEP is prescription-only. Ask a primary-care provider, a sexual-health or STI clinic, an HIV/PrEP clinic, or a telehealth sexual-health service. This tool is informational and cannot prescribe it, bring your result to that conversation.
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