PEP after exposure, and PrEP, on Koh Phi Phi
Two medications, two completely different situations, and one hard deadline. PEP is taken after a possible exposure and must start within 72 hours. PrEP is taken beforehand by people at ongoing risk. PEP and PrEP in Koh Phi Phi are both available here at any hour — and if you are reading this because something happened last night, stop reading and come in.
PEP: the 72-hour rule
Post-exposure prophylaxis is a 28-day course of antiretroviral medication that can prevent HIV from establishing itself after a possible exposure.
The deadline is genuine rather than cautious. It works best within a few hours, remains effective within 24, declines through 48 and 72, and is not offered beyond 72 hours because the evidence no longer supports it. There is no negotiating with that number.
Every hour spent deciding is an hour of effectiveness. This is the clearest single reason both branches run through the night: on an island where the last boat has gone by evening, having to wait for morning would spend eight or ten hours of the window on nothing at all.
If you are unsure whether your situation qualifies, come and ask rather than working it out from a website at four in the morning. The consultation costs little, the answer takes minutes, and the alternative is a decision you cannot revisit later.
What counts as needing PEP
The main ones:
- Unprotected anal or vaginal sex with somebody whose status you do not know
- A condom that broke or slipped during sex with a partner of unknown status
- Sexual assault
- Sharing needles or injecting equipment
- A needlestick injury, including tattoo and piercing equipment
Risk varies considerably between these, and part of the consultation is working out whether the exposure carries enough risk to justify a month of medication with side effects. Sometimes the honest answer is that it does not, and we will say so rather than prescribing to be safe.
What taking PEP is actually like
A baseline HIV test first, because PEP is the wrong treatment for somebody already positive, plus kidney and liver function checks — see blood tests.
Then one tablet daily for 28 days, without missing doses. That last part matters more than anything else — interrupted courses are the main reason PEP fails, and it is a month, not a week.
Side effects are usually mild with modern regimens: some nausea, headache and tiredness in the first days, generally settling. Follow-up testing happens at the end of the course and again at three months.
You can start here and continue elsewhere. The medication is widely available across Thailand and internationally, and you get a written record so the next clinic continues rather than restarts.
Finishing the course after you leave
Most people who start PEP here are on a two-week holiday, which means half the course happens somewhere else. That is normal and it is planned for rather than improvised.
You leave with the written record, the exact dates, and the generic name of the medication rather than a Thai brand name that means nothing to a pharmacist at home. Take a photograph of all of it.
The failure mode is running out mid-course while travelling — a missed week is worse than a late start. Work out before you leave the island where the next supply comes from, and if the answer is unclear, tell us and we will help you plan around it.
PrEP: prevention rather than reaction
Pre-exposure prophylaxis is medication taken before any exposure by people at ongoing risk. Taken properly it reduces the chance of acquiring HIV sexually by well over ninety per cent.
It is worth considering if you have multiple partners, if condom use is inconsistent in practice rather than in intention, if you have a partner who is HIV positive, or if you have already needed PEP once. That last one is the clearest signal of all — needing PEP is a reasonable argument for not needing it again.
Thailand has one of the most established PrEP programmes in the region, and it is neither unusual nor difficult to arrange.
Starting and staying on PrEP
You need a negative HIV test first — taking PrEP while unknowingly positive risks drug resistance — plus kidney function and hepatitis B testing.
Daily dosing is the standard and works for everybody. Event-based dosing, sometimes called 2-1-1, is an alternative for some people and involves a specific schedule around a planned exposure; it is not suitable for everyone and needs explaining properly rather than summarising here.
Ongoing, it means an HIV test every three months and periodic kidney checks. If you are here for a season that is manageable on the island; if you are moving on, the monitoring continues wherever you are.
What neither of them does
Both prevent HIV. Neither prevents anything else — not chlamydia, gonorrhoea, syphilis, herpes or hepatitis, and not pregnancy.
Rates of other sexually transmitted infections are meaningfully higher among people on PrEP, largely because condom use tends to drop. That is not an argument against PrEP; it is an argument for continuing to test for the rest on a regular schedule.
Nor does either protect against hepatitis B, which is worth a separate thought on this island given how many people get a tattoo here on impulse. That one has a vaccine and it is cheap — see travel vaccinations.
Cost, discretion and being on an island
Both are quoted before anything starts. PEP is a month of medication and is not trivial in cost, though considerably cheaper in Thailand than in most Western countries. PrEP is a recurring cost and is inexpensive here by international standards.
Everything is confidential in the same way the rest of our sexual health work is: results to you alone, nothing shared with your hotel, your companions or immigration, and no reason for the visit stated where anybody can see it.
One practical note about geography. If something happens at three in the morning, come in then — do not wait for a decent hour. And if you cannot get to either clinic, ask for a doctor hotel visit. On a seventy-two hour clock, starting the conversation now rather than at breakfast is worth real effectiveness.
Frequently asked questions
How long do I have to start PEP?
72 hours from the exposure, and sooner is substantially better. It is not offered after 72 hours.
Can I come in at 3am for this?
Yes, and you should. Both branches are staffed around the clock precisely because this treatment runs on a clock of its own.
How long is the PEP course?
28 days of daily tablets, without missed doses. Interrupted courses are the main reason it fails.
Can I start PEP here and finish it at home?
Yes, and most people do. You get a written record with dates and the generic drug name, and the medication is widely available internationally.
Is PrEP hard to get in Thailand?
No. Thailand has one of the region’s most established PrEP programmes and it is straightforward to arrange.
Do PEP or PrEP protect against other infections?
No. Both prevent HIV only — not other sexually transmitted infections, not hepatitis B, and not pregnancy.
What are the side effects?
Usually mild with modern medication — some nausea, headache and tiredness early on, generally settling within days.
What if I run out mid-course while travelling?
A missed week is worse than a late start. Plan the next supply before you leave the island, and tell us if it is unclear so we can help you work it out.
The island arithmetic, and where we fit in it
English-speaking doctors on site, 24 hours a day. It is worth spelling out why that matters rather than leaving it as a claim. Koh Phi Phi has no hospital, no road connection and no ambulance service. Getting to an emergency department means a boat, and the scheduled boats run in daylight — so for a good part of every twenty-four hours, the island’s own clinic is not the convenient option, it is the only one. Everything about how we are staffed follows from that single fact.
Beyond the island, Doctor Phi Phi Takecare Clinic belongs to the Takecare Clinic group, which operates across Krabi and Phuket. The practical value of that is continuity: if your treatment carries on after you leave, the next clinic already holds your notes, and a referral is a phone call between colleagues rather than a stack of paperwork you have to carry yourself.
Coming in
Doctor Phi Phi Takecare Clinic is 24 hours, every day, and that is the building being open with a doctor in it rather than a phone line that answers. No appointment is needed at any point, and there is no hour at which turning up is inconvenient for us. There are 2 branches on the island, about ten minutes apart on foot, and both keep the same hours — so head for whichever is closer rather than looking for the right one. Walk in, or reach us on +66 82 140 3858 or WhatsApp. If you would rather not move, ask for a doctor hotel visit and we will come to you.
If it turns out this is beyond what the island can treat, the same conversation is where the boat and the hospital transfer start being arranged. That process is worth beginning early rather than late here, because the options genuinely narrow as the evening goes on — and a decision made at nine is a considerably better decision than the same one made at two in the morning.