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Patient instructions

HIV Post-Exposure Prophylaxis (PEP) Patient Instructions

These instructions are for the 28-day HIV post-exposure prophylaxis kits dispensed after a potential exposure. Taken correctly, PEP is highly effective at preventing HIV infection — the two things that matter most are starting fast and finishing all 28 days. Available by prescription only.

Every day, 28 days

PEP only works as a complete course. Stopping early — even in the last week — undermines the protection the first weeks built.

The first two weeks are the hardest

Nausea, tiredness, and headache are common at the start and usually fade. Do not stop on your own — call us; side effects can almost always be managed.

Check before adding anything

Some antacids, multivitamins, and mineral supplements block the absorption of PEP medications. Check with the pharmacy before taking anything new — including over-the-counter products.

Taking the Course

  1. 1Take the first dose as soon as you have the kit, if the clinic has not already given it. PEP works best started within hours of the exposure, and must start within 72 hours.
  2. 2Take every dose, every day, for the full 28 days, at roughly the same time of day. Set a daily phone alarm now.
  3. 3Taking doses with food helps with nausea — the most common early side effect.
  4. 4If you miss a dose and remember the same day, take it when you remember and continue as usual. Never take a double dose. If you miss a full day, keep going and call the clinic or pharmacy.
  5. 5If you vomit within an hour of a dose, call the pharmacy before deciding whether to repeat it.

Follow-Up

  • Keep every follow-up appointment the clinic books — testing typically happens at baseline, around 4 to 6 weeks, and again around 3 months.
  • Use condoms and avoid donating blood until the clinic confirms your final test results.
  • If the exposure involved another person whose status becomes known, tell the clinic — it can change the plan.

Early side effects — nausea, tiredness, headache — are common in the first week or two and usually settle. They are not a reason to stop. If they are interfering with your doses, call the pharmacy; timing, food, and supportive options usually solve it.

When to Call the Pharmacy or Clinic

  • Side effects are making it hard to keep taking the doses.
  • You missed a full day or more.
  • You are about to start any new medication, supplement, or antacid.
  • You are running low or a dose is damaged or lost — the course cannot have gaps, so call right away.