Who should take PrEP? Anyone, of any gender or sexuality, whose sex life or drug use gives them a real chance of coming into contact with HIV, including straight people, couples and trans people, not only gay men.
PrEP is a pill that HIV-negative people take to stay negative. When taken as prescribed, the CDC says it reduces the risk of getting HIV from sex by about 99% and from injecting drug use by at least 74%. The question is less about who you are and more about what is happening in your life right now.
What “substantial risk” means in everyday words
The World Health Organization recommends PrEP for people at substantial risk of HIV. That phrase sounds clinical, but in practice it means your chance of meeting HIV is high enough that a daily or on-demand pill makes a real difference.
The WHO fact sheet lists the things that raise HIV risk: condomless anal or vaginal sex, having another STI, and sharing injecting equipment. If one of these describes the past few months or the months ahead, PrEP is worth a conversation.
There is no score sheet that decides who should take PrEP. A doctor will usually ask about the last few months and the months ahead: new partners, condom use, recent STIs and any PEP. Honest answers simply help match the protection to your life, and nothing you say is a test you can fail.
PrEP is not only for gay men
A common belief is that HIV PrEP is only for men, or only for gay men. It isn’t. Gay and bisexual men are a large share of PrEP users in Thailand and elsewhere, but the medicine works for everyone it is prescribed for.
- Straight men and women: yes, PrEP is for straight people too. Heterosexual sex accounts for many HIV infections worldwide.
- Women: daily PrEP protects during vaginal sex once it has built up, which takes about 21 days.
- Trans women and trans men: PrEP is suitable, and gender-affirming hormones are not a reason to avoid it.
- Gay and bisexual men: protection for receptive anal sex builds after about 7 days of daily pills.
If you are a straight man who has been told PrEP is “not for you”, that is out of date. PrEP for straight people works the same way; what matters is exposure, not identity. You can read more about how PrEP works in the body on our homepage.
Situations where PrEP is worth discussing
Below are the situations doctors hear about most. None of them is a judgement; they are simply the times when PrEP adds real protection.
Common situations and whether PrEP fits
| Situation | Worth discussing PrEP? | Why |
|---|---|---|
| New or casual partners, condoms not always used | Yes | Status of partners often unknown |
| Partner of unknown HIV status | Yes | You cannot rely on their result |
| Partner with HIV whose viral load is not yet undetectable | Yes | Bridges the gap until treatment works |
| A recent STI, such as syphilis | Yes | Signals exposure and raises HIV risk |
| Sex work or transactional sex | Yes | More partners, less control over condoms |
| Sharing needles or injecting equipment | Yes | Direct blood exposure |
Straight couples often fall into the second row. Perhaps one partner travels for work, or neither of you has tested recently. Considering PrEP in that situation is a practical step, not an accusation.
If you keep needing PEP
PEP is the emergency course of HIV medicine you start within 72 hours after a possible exposure. If you have needed PEP more than once in a year, that pattern is one of the clearest signs that PrEP would suit you better.
Moving straight from PEP to PrEP is common; our step-by-step guide to switching from PEP to PrEP without a gap explains the handover. A doctor confirms you are still HIV negative at the end of your PEP course and you begin PrEP without a break. Our guide on starting and stopping PrEP safely explains how the switch works.
Exposed in the last 72 hours? You need PEP, not PrEP. Contact us for urgent PEP as soon as possible.
When PrEP probably isn’t needed
PrEP is a choice, not an obligation. Some people simply don’t need it, and a good clinic will tell you so.
PrEP, condoms and a partner on treatment compared
| Approach | Protects against HIV | Protects against other STIs |
|---|---|---|
| PrEP taken as prescribed | Yes, very well | No |
| Condoms used every time | Yes, when used correctly | Yes, for many STIs |
| Partner with HIV and an undetectable viral load | Yes, HIV is not passed on through sex | No |
| Both partners tested, sex only with each other | Yes, while that stays true | Yes, while that stays true |
So, do you need PrEP if you use condoms? If you use them every time and they rarely slip or break, you may not. Many people add PrEP because real life is less tidy than that, and it covers the times a condom isn’t used.
Your needs can also change over time. Plenty of people take PrEP during a stretch of dating or travel, stop once they settle into a tested, closed relationship, and restart later if things change. Working out who should take PrEP is never a decision made once and for all; it is worth revisiting whenever your circumstances shift.
Who can take PrEP, and who needs extra checks
Most adults who are HIV negative can take PrEP. A few things change the advice, which is why every start includes tests.
- Kidney problems: tenofovir is cleared by the kidneys, so your doctor checks function first and over time.
- Hepatitis B: you can still take daily PrEP, but 2-1-1 is not suitable and stopping needs medical advice.
- Pregnancy or breastfeeding: daily PrEP can be used after a discussion with your doctor.
- Trans women on estradiol: daily PrEP is recommended rather than 2-1-1.
On-demand 2-1-1 PrEP is only for cis men who have sex with men and trans women not taking estradiol-based hormones. It is not for vaginal or front-hole sex. Our 2-1-1 PrEP planning calculator explains the timing if you are eligible.
Before starting, you will need an HIV test, a kidney check and a hepatitis B test; our guide to the tests before and during PrEP covers each one. If you are working out who needs to take PrEP in your household or relationship, try our 1-minute PrEP self-check first, then book a PrEP consultation with our doctors.
Questions people ask
Who should take PrEP for HIV?
Anyone who is HIV negative and has a real chance of exposure through sex or shared injecting equipment. Gender and sexuality don’t decide it; your situation does.
Is HIV PrEP only for men?
No. Women, trans people and straight men can all take daily PrEP. Only the 2-1-1 schedule is limited to certain groups.
Is PrEP for straight couples?
Yes, if one partner may be exposed, for example through other partners, or if a partner’s status is unknown. Many straight couples use it.
Do I need PrEP if I use condoms?
Not necessarily. If you use condoms every time, your HIV risk is already low. PrEP covers the times they are not used.
Where can I get PrEP and how much does it cost?
Our guides on getting PrEP in Thailand and typical PrEP prices in Bangkok explain the routes and approximate costs.
Written by the HIV PrEP Bangkok team, based on WHO and CDC guidance. Last updated 2 October 2026.