Guidance varies by country. CDC describes event-driven oral PrEP as off-label and does not recommend it; recommendations elsewhere must be checked with a qualified local service. This article is not a pill schedule or proof of approval in Thailand. [1]
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. [1]
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. [1]
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. [1]
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. [1]
What should happen before and during PrEP?
- Confirm HIV-negative status before starting [1]
- Discuss the most recent possible exposure [1]
- Review kidney health, hepatitis B, pregnancy, and other medicines as relevant [1]
- Arrange HIV and sexual-health follow-up [1]
- Ask what to do after missed or changed timing [1]
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. Seek PEP assessment as soon as possible after a possible HIV exposure and start when indicated within 72 hours. Do not wait for symptoms, all pending laboratory results or an online appointment. If more time has passed, still seek assessment and a testing plan; do not substitute PrEP yourself. [2]
Does PrEP prevent other STIs?
PrEP prevents HIV, not other STIs or pregnancy. It is not a guarantee against every HIV exposure; discuss the suitable product, testing and follow-up with a provider. [1]
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. [1]
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. [1]
Sources
หมายเหตุ บทความนี้ให้ข้อมูลความรู้ทั่วไป ไม่ใช่การวินิจฉัย และไม่ใช่คำแนะนำการใช้ยาเฉพาะบุคคล เรื่องยาและการรักษาเป็นการตัดสินใจร่วมกับแพทย์หรือเภสัชกรที่ดูแลคุณ ไม่ควรซื้อ เริ่ม หยุด หรือปรับยาด้วยตัวเอง หากมีข้อสงสัยเกี่ยวกับสุขภาพของตัวเอง ปรึกษาเจ้าหน้าที่สาธารณสุขหรือคลินิกใกล้บ้านได้เสมอ
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