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
Common questions
How soon after unprotected sex can I test for STIs?
Sooner than you want to wait - but not immediately, and that is the mistake that produces false reassurance. Each infection has a window before tests can find it: chlamydia and gonorrhea are usually detectable by about 1 to 2 weeks after exposure; syphilis blood tests typically need 3 to 6 weeks and can take up to 3 months; for HIV, the window depends on the test type, per the CDC: antibody tests (including most rapid and home tests) detect infection 23 to 90 days after exposure, while a lab antigen/antibody test works at 18 to 45 days and a NAT at 10 to 33 days. The smart pattern after a concerning exposure: get a baseline test now (it establishes your starting point and catches anything older), then retest at the windowed times - around 2 weeks for the bacterial infections and 6 weeks to 3 months for syphilis and HIV, depending on test type. Two urgencies jump the queue: symptoms now mean test now, and a possible HIV exposure within the last 72 hours means PEP is a same-day emergency-room conversation, not a testing one. Pymander, a free AI doctor available 24/7 by text, can map the schedule to your timeline.