PEP and PrEP in 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 single clearest reason the clinic runs 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 a seventy-two hour window on nothing at all.
If you are unsure whether your situation qualifies, come and ask rather than working it out yourself 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 someone 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.
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.
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 everyone. 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.
If you want protection against the full range, condoms remain the only thing that covers it.
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 anyone 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 the 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. The clinic is 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. You get a written record 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 and not pregnancy.
What are the side effects?
Usually mild with modern medication — some nausea, headache and tiredness early on, generally settling within days.
Who treats you, and at what hour
English-speaking doctors on site, 24 hours a day. That is the part worth dwelling on, because Koh Phi Phi has no hospital and no road off it. The nearest emergency department is a ferry away on the mainland, and the ferries stop at night — so between roughly sunset and morning, a clinic that is actually open is the only medical care on the island. We are part of the Takecare Clinic group operating across Krabi and Phuket, which is what makes onward referral and continuing treatment on the mainland straightforward rather than something you arrange yourself from a hotel room.
Getting seen
Doctor Phi Phi Takecare Clinic is 24 hours, every day — genuinely, not as a phone line. No appointment is needed at any point and there is no wrong time to turn up. 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. And if this turns out to be beyond what the island can handle, that same call is how the ferry and the hospital transfer start being arranged — which on Phi Phi is a process worth starting early rather than late.