Getting treated is only half of it: knowing when you're clear to have sex again, and when to check for reinfection, is what actually keeps an STI from coming back. Pick what you were treated for and your treatment date below, and the calculator maps both dates for you (and can drop reminders straight into your calendar).

When is it safe to have sex again?

For chlamydia, gonorrhea, and trichomoniasis, the CDC's rule is simple: wait 7 days after single-dose treatment (or until you finish a 7-day course), until symptoms clear, and until your partner(s) have been treated. Skipping any of those is the most common reason an infection seems to “come back”: it's usually reinfection from an untreated partner, not treatment failure.

For syphilis, wait until treatment is complete and any sores have fully healed, and until partners are evaluated, then follow the blood-test schedule your provider sets.

Retest vs. test of cure, which do you need?

  • 3-month retest, almost everyone. Because reinfection is so common, the CDC recommends retesting ~3 months after treatment for chlamydia, gonorrhea, and trichomoniasis. It checks for a new infection, not the old one.
  • Test of cure, only sometimes. A test to confirm the infection cleared is only advised for throat gonorrhea (7–14 days after treatment), chlamydia in pregnancy, or if symptoms don't resolve. The medicines otherwise work reliably.

Treatment gives you no immunity, you can catch the same STI again the day after you're cured. Retesting, treating partners, and prevention (condoms, doxy-PEP if you qualify) are what keep it from coming back. Whether an STI can be cleared for good in the first place depends on whether it's bacterial or viral.

Keep exploring on EasySTD: when to re-test, what STD testing costs and Chlamydia testing.