Compare the options at a glance
All three PrEP options prevent HIV very well when used correctly; the right one depends on your body, the sex you have and the routine you can keep.
Daily, 2-1-1 and injectable PrEP compared
| Point | Daily tablets | On-demand 2-1-1 | Cabotegravir injection |
|---|---|---|---|
| How you take it | One tablet a day | 4 tablets around each episode of sex | Injection every 2 months after two starting doses |
| Who it suits | Everyone eligible | Cis men who have sex with men; trans women not on estradiol | People who struggle with tablets and can keep appointments |
| Vaginal or front-hole sex | Yes | No | Yes |
| With hepatitis B | Yes, with monitoring | No | Ask your doctor |
| Clinic visits | About every 3 months | About every 3 months | Every 2 months |
| Availability with us | Yes | Yes, if eligible | Ask us |
When each option starts protecting you
Time to protection by option
| Option | Anal sex | Vaginal or front-hole sex |
|---|---|---|
| Daily tablets | About 7 days | About 21 days |
| 2-1-1 | 2–24 hours after the double dose | Not suitable |
| Cabotegravir | Ask your doctor about cover while it builds up | Ask your doctor about cover while it builds up |
Protection figures for tablets come from CDC guidance. Our guide to how effective PrEP is explains what affects them.
Choosing the right option
- Choose daily PrEP if you want the simplest, most forgiving routine, have vaginal or front-hole sex, have hepatitis B or take estradiol. Read starting and stopping PrEP safely.
- Consider 2-1-1 if you’re eligible, sex is occasional and usually planned, and you’re confident about timing. The 2-1-1 dose planner turns one date into a full schedule.
- Ask about injections if daily tablets keep slipping and you can attend every two months. See injectable PrEP in Bangkok and the lenacapavir outlook for Thailand.
You aren’t locked in: many people switch between daily and on-demand dosing as their life changes, after talking it through at a check-up. Women and trans people have specific advice in PrEP for women and PrEP with gender-affirming hormones.
Brands and costs
Daily and 2-1-1 PrEP use the same tablet. In Thailand that’s usually a generic such as Teno-EM, Tenof-EM or Ricovir-EM, with the same ingredients as Truvada; see generic PrEP in Thailand. On-demand dosing uses fewer tablets if sex is occasional, while injections cost far more. Approximate prices are in our PrEP cost guide, and eligible Thai citizens can read about free PrEP in Thailand.
Not sure yet?
Take the five-question PrEP self-check, read what PrEP is and how it works, or book a PrEP consultation and decide with a doctor.
Written by the HIV PrEP Bangkok team, based on WHO and CDC guidance. Last updated 2 October 2026.