How soon after unprotected sex can I test for STIs?
Last updated September 3, 2026.
Not immediately - each infection has a window before tests can find it, and testing inside the window produces false reassurance. Chlamydia and gonorrhea: about 1 to 2 weeks. Syphilis: typically 3 to 6 weeks, up to 3 months. HIV depends on the test, per the CDC: antibody tests 23 to 90 days, lab antigen/antibody 18 to 45 days, NAT 10 to 33 days. The smart pattern: baseline test now, retest at the windowed times. Two urgencies jump the queue - symptoms now, and possible HIV exposure within 72 hours, which is a same-day PEP conversation.
What to do
- Baseline now, retest on schedule. One negative inside the window is not an answer.
- Learn the per-infection windows. Bacterial: weeks. Syphilis and HIV: weeks to months by test type.
- Symptoms skip the schedule. Sores, discharge, burning: test now.
- Under 72 hours after possible HIV: PEP. Same day, emergency room or clinic - not next week.
Related questions
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