PEP (Post-Exposure Prophylaxis) is an intensive antiretroviral regimen taken for 28 days to stop HIV from establishing an infection after a potential exposure.

It works. But it sucks.

Do I Need PEP? Quick Assessment

Answer these three questions in order. Stop as soon as you have your answer.

Question Answer Action
Are you already on PrEP and took it consistently? Yes ✅ No PEP needed for HIV. Your protection held. Check DoxyPEP for bacterial STIs.
Was the exposure oral sex only? Yes ✅ No PEP needed. HIV transmission risk from oral sex is extremely low.
Is the other person HIV-positive AND confirmed undetectable (U=U)? Yes ✅ No PEP needed for HIV. Zero transmission risk.
None of the above apply — condom broke, unprotected sex with unknown status, or assault — ⚠️ Get PEP. You have 72 hours. Act now.
❗ Important

If you're unsure, act as if you need it. You can always stop at the clinic and find out you don't need it. You can't go back and start PEP 73 hours after exposure.

The Protocol

  • Time Window: You must start within 72 hours (3 days).
    • Ideal: Within 4 hours.
    • Okay: Within 24 hours.
    • Risky: Hour 71.
  • Duration: 28 days. Every single day. Same time. No misses.

What You'll Actually Be Given

The current preferred regimen (per WHO and most national guidelines) is:

Truvada (TDF/FTC) + Tivicay (dolutegravir)

Dolutegravir has replaced raltegravir (Isentress) as the first-line choice because it's once-daily, better tolerated, and has a higher barrier to resistance. You may still be prescribed raltegravir (Isentress) at some clinics, particularly if dolutegravir isn't in stock—it works, but requires twice-daily dosing.

  • If you're already on injectable PrEP (cabotegravir): Tell the prescribing doctor—standard oral PEP may need to be adjusted. Seek specialist advice immediately.

The Reality of "The Month from Hell"

PEP is not PrEP. The drug load is heavier and the consequences of stopping are severe.

1. The Side Effects

Common reactions include:

  • Intense nausea / Vomiting
  • Diarrhea (The "PEP Trots")
  • Fatigue / Brain fog
  • Insomnia

The Risk: Many guys stop at Day 10 because they feel sick. If you stop early, the virus can win.

2. The "Vomit Hazard"

  • If you throw up within 1–2 hours of taking your pill: YOU MUST TAKE ANOTHER ONE.
  • The pill didn't digest. If you don't redose, you missed a day.
  • Tip: Keep anti-nausea meds (Zofran / ondansetron) on hand. Ask your prescribing doctor for a supply when they give you PEP.

3. The Anxiety

The uncertainty during PEP is real—you won't have a definitive answer until follow-up testing. The psychological toll can be heavier than the physical side effects. This is normal, and it doesn't mean something is wrong with you.

Perspective: PEP is highly effective when started promptly. The odds are strongly in your favour. And even in the unlikely event of a positive result—HIV is a manageable chronic condition with modern treatment, not a death sentence. You are going to be okay either way.

When to Use It

  • Condom broke (and you are NOT on PrEP).
  • Unprotected sex with someone whose status you don't know (and you are NOT on PrEP).
  • Sexual assault.

If you are already on PrEP and took it correctly: You do not need PEP for HIV. Your wall held.

The Bottom Line

PEP is a miracle. It saves lives. But it is a fire extinguisher, not a lifestyle. If you've needed PEP more than once, that's not a failure—it's data. It means your exposure pattern would be better covered by PrEP, which is easier on your body, more effective, and puts you in the driver's seat instead of the ER waiting room. Talk to your doctor about switching to proactive protection.

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