Possible HIV Exposure: PEP Within 72 Hours
Medically reviewed by our MD Laboratory Director (a role required by CLIA; the director's name is on file in the CMS CLIA database, #45D2048957, and can be verified independently) · Editorial policy
72 hours. PEP started sooner works better. Do not wait for a test result to act.CLIA #45D2048957 · CAP #8722734 · Same-day results · Walk-ins welcome
Two things, in this order. First: seek care for post-exposure prophylaxis (PEP) immediately — CDC states PEP must be started within 72 hours of exposure, and effectiveness falls the longer you wait. Second: get a baseline test. A test taken today cannot tell you whether last night infected you — it establishes where you started.
Not sure what you need? Text us and we will set it up.
📱 Text (713) 832-8892 📞 Call (713) 266-0808
📱 Text (713) 832-8892 📞 Call (713) 266-0808
3707 Westcenter Dr Suite 100, Houston, TX 77042 · Walk-ins welcome
Why the test is not the emergency
| Hours since exposure | Priority |
|---|---|
| 0–72 hours | PEP evaluation — urgent. Baseline testing alongside it |
| After 72 hours | PEP is no longer indicated. Testing per the window period becomes the plan |
| 18–45 days | 4th-generation antigen/antibody test becomes reliable |
| 3 months | Definitive answer |
A negative HIV test the morning after an exposure is not reassurance. It is a baseline. The exposure you are worried about could not possibly be detectable yet.
What counts as an exposure worth acting on
Condomless sex with a partner of unknown or positive status, a broken condom, a needle-stick or shared injection equipment, or sexual assault. If you are unsure whether it qualifies, that uncertainty is itself a reason to be evaluated today rather than to search the internet at 3 AM.
We name drugs, never doses. Treatment statements follow CDC guidance; dose and duration are decided by a licensed physician who has your result and your history.
Same day, start to finish. Sample by 1:00 PM → results at 4:30 PM → if treatment is clinically appropriate, a licensed physician in our partner network sees you between 4:30 and 6:00 PM, a few minutes away. That window is reserved for patients tested here, and your slot is held the moment we take your sample — the slot is held, not hunted. On your own, a same-day appointment is nearly impossible; at an urgent care, you wait in the queue. STAT: ~2 hours, sample in by 3:00 PM.
FAQ
- Where do I get PEP?
- An emergency department, an urgent care, or a physician can start it. Do not delay this while arranging a test — the 72-hour clock is running.
- Should I still test here?
- Yes — a baseline today, then follow the window-period timeline. We will map the dates out for you.
- What about other infections from the same exposure?
- Test for chlamydia, gonorrhea, trichomonas and syphilis at the appropriate intervals. Sites matter — see the site guide.
- Is PEP the same as PrEP?
- No. PEP is emergency treatment after an exposure. PrEP is ongoing prevention before one. Ask a physician about both.
Not sure what you need? Text us and we will set it up.
📱 Text (713) 832-8892 📞 Call (713) 266-0808
📱 Text (713) 832-8892 📞 Call (713) 266-0808
3707 Westcenter Dr Suite 100, Houston, TX 77042 · Walk-ins welcome