On-demand PrEP is an event-based way of using oral PrEP around planned sexual exposure. It is not suitable for every person, every type of exposure, or every PrEP product, so it should begin with HIV testing and an individual assessment.
This is general information and does not replace personal advice from a PrEP provider. Do not buy, start, stop, share, or change PrEP medicine on your own.
How is on-demand PrEP different from daily PrEP?
Daily PrEP follows a regular schedule and may suit people who prefer routine protection or cannot predict exposure. On-demand PrEP follows an event-based plan and requires advance planning. The safest choice depends on the medicine available, route of exposure, health, and current guidance.
Who should ask a clinic before choosing it?
Everyone should be assessed before starting, especially people with a recent possible HIV exposure, an unclear HIV result, hepatitis B, kidney concerns, pregnancy, or medicines and supplements that may interact. Evidence and recommendations are not identical for all populations.
Why is there no pill schedule here?
A short number-based formula can be unsafe when copied without checking the product, timing, HIV status, or personal health. A PrEP clinic can provide the correct written plan for the medicine and situation, including what to do if timing changes.
What should happen before and during PrEP?
- Confirm HIV-negative status before starting
- Discuss the most recent possible exposure
- Review kidney health, hepatitis B, pregnancy, and other medicines as relevant
- Arrange HIV and sexual-health follow-up
- Ask what to do after missed or changed timing
Read about HIV self-testing and why Doxy-PEP is different from HIV PrEP.
Frequently asked questions
Can on-demand PrEP be used after an exposure?
No. A recent possible exposure may need urgent assessment for HIV PEP instead.
Does PrEP prevent other STIs?
No. It prevents HIV, not syphilis, gonorrhoea, chlamydia, herpes, HPV, or pregnancy.
Can I switch between daily and on-demand plans myself?
No. Ask a PrEP provider how to change safely without leaving a gap in protection.
Summary
On-demand PrEP can be a useful option for some people, but it is not a universal shortcut. Start with testing, receive a written plan for the correct product, and keep follow-up appointments.
