Doxy-PEP
Doxy-PEP is an antibiotic treatment that, when taken after sex, significantly reduces your risk of acquiring certain sexually transmitted infections (STIs), primarily syphilis and chlamydia.
Doxy-PEP involves taking 200mg of doxycycline within 72 hours after sex to prevent syphilis and chlamydia. While it requires a prescription from a GP or specialist, Doxy-PEP offers substantial protection when used correctly as part of a comprehensive STI prevention strategy.
How effective is Doxy-PEP?
Research shows that Doxy-PEP reduces syphilis infections by 70-80% and chlamydia by 70-90% among gay, bisexual, and other men who have sex with men. However, its effectiveness against gonorrhoea is limited due to antibiotic resistance, with some studies showing 45% reduction in Australia while others show minimal effectiveness.
Doxy-PEP does not protect against viral infections such as HIV or herpes, so maintaining other prevention strategies remains crucial for comprehensive sexual health protection.
While Doxy-PEP prevents certain bacterial STIs, it doesn’t replace regular STI testing, safe sex practices, or HIV prevention methods like PrEP. Think of it as an additional layer of protection rather than a complete solution.
Who should consider Doxy-PEP?
Doxy-PEP has been specifically researched and recommended for gay, bisexual, and other men who have sex with men, as well as transgender women who are at higher risk of bacterial STIs. The greatest benefits are seen in those with specific risk factors.
When to think about taking Doxy-PEP
You might be a good candidate for Doxy-PEP if you:
- Have been diagnosed with syphilis in the past 6-12 months
- Have had two or more bacterial STI diagnoses recently
- Are planning periods of increased sexual activity (events, holidays, travel)
- Have both male and female sexual partners
- Are already taking PrEP and want additional STI protection
The prevention of syphilis deserves particular attention due to its serious health complications, especially among men who have sex with men living with HIV. Syphilis can cause significant long-term health issues if left untreated, making its prevention particularly valuable.
When to consider Doxy-PEP
Doxy-PEP may be considered during:
- Periods of high syphilis transmission in the community
- Attendance at sex-on-premises venues or events
- Travel periods involving casual sexual encounters
- Times when you’re having more frequent unprotected sex
- Periods when regular STI testing might be challenging
How do I take Doxy-PEP?
Taking Doxy-PEP correctly is essential for it to work effectively. The timing and dosage are specific, and following the guidelines ensures maximum protection while minimising side effects.
Standard dosing: Take 200mg of doxycycline (two 100mg tablets) within 72 hours after sex. The sooner you take it after sex, the more effective it will be, but it can still provide protection up to three days later.
It is important to not share your Doxy-PEP with friends or partners.
Important Doxy-PEP timing rules
- Don’t take Doxy-PEP more than once every three days
- If you have multiple sexual encounters over a weekend, one dose on Monday morning covers all weekend activity
- You don’t need separate doses for each sexual encounter within a 72-hour period
Taking Doxy-PEP safely
- Swallow tablets with a full glass of water or milk
- Take with food if you experience stomach upset
- Stay upright for at least 30-60 minutes after taking to prevent throat irritation
- Apply sunscreen when outdoors as doxycycline increases sun sensitivity
What to avoid
- Don’t take antacids, iron, calcium, or zinc supplements within 2 hours of doxycycline
- Avoid excessive sun exposure without protection
- Don’t lie down immediately after taking the tablets
Doxy-PEP and other medications
It is safe to take Doxy-PEP at the same time as PrEP, PEP, or other HIV treatments. Doxy-PEP can also be used alongside PEP if you’ve had a potential HIV exposure. Your doctor can prescribe both medications together and advise on any timing considerations.
There are some medications such as antiepileptic medications and the acne medication isotretinoin (Roaccutane) that must not be taken with doxycycline.
If you’re not sure, discuss it with your doctor – always inform your healthcare provider about all medications and supplements you’re taking to ensure there are no interactions or contraindications.
How to get Doxy-PEP
Getting Doxy-PEP in Perth requires a prescription from a GP or sexual health specialist. Many doctors are now familiar with prescribing Doxy-PEP in Perth, and resources are available to help guide the conversation if your doctor needs additional information.
Where to get a prescription for Doxy-PEP in Perth
- Your regular GP (if they’re comfortable prescribing it)
- Sexual health clinics (like us!)
- HIV specialists (S100 prescribers)
- LGBTQIA+ friendly medical practices
Cost considerations: Doxy-PEP is not currently subsidised under the PBS, so you’ll pay the full cost of the medication. Prices vary between pharmacies, so it’s worth shopping around. A typical prescription will cost around $23 for 28 tablets.Your regular GP (if they’re comfortable prescribing it)
Monitoring and follow-up care
Regular monitoring is important when using Doxy-PEP to ensure it remains appropriate for your circumstances and to watch for any side effects or complications.
Regular check-ups should include:
- STI testing every 3-6 months (or more frequently if recommended)
- Review of your ongoing need for Doxy-PEP
- Discussion of any side effects or concerns
- Review of any new medications
- Updates to your sexual health plan as circumstances change
Always tell any other prescribers that you are on doxycycline.
It is recommended to use Doxy-PEP for a pre-defined period, e.g., 3–6 months, followed by review of the need for ongoing use. Your risk factors and sexual practices may change over time, making regular reassessment important.
Doxy-PEP and STI testing
Continued STI testing is essential when taking Doxy-PEP because:
- Monitoring helps track the effectiveness of your prevention strategy
- Doxy-PEP doesn’t prevent all STIs
- Resistance can develop over time
- Early detection and treatment remain important for overall sexual health
What are the side effects of Doxy-PEP?
Like all medications, Doxy-PEP can cause side effects, though most people tolerate it well when taken correctly. Understanding potential side effects helps you use the medication safely and know when to seek medical advice.
Common side effects of Doxy-PEP
Common side effects of Doxy-PEP include:
- Increased sun sensitivity (higher risk of sunburn)
- Mild stomach upset or nausea
- Headache
- Changes to gut bacteria (which usually resolve after stopping)
Rare side effects of Doxy-PEP
Rare but serious side effects include:
- Severe allergic reactions
- Oesophageal irritation or ulceration (prevented by staying upright after taking)
- Liver problems (very rare)
- Angioedema – swelling of the oral or genital mucosa
When to contact your doctor
You should contact your doctor immediately if you experience:
- Severe stomach pain or persistent nausea
- Difficulty swallowing or chest pain after taking tablets
If you’re not sure, it is always better to be safe and to contact your doctor or go to the hospital if you experience any adverse reactions.
Doxy-PEP and antibiotic resistance
One important consideration with Doxy-PEP use is the potential for antibiotic resistance. This means bacteria can become less responsive to antibiotic treatment over time, which could affect both individual and community health.
What we know:
- Overuse of antibiotics can lead to resistant bacterial strains
- Gonorrhoea already shows significant resistance to many antibiotics
- The impact of widespread Doxy-PEP use on resistance patterns is still being studied
- Responsible use and monitoring are essential
Minimising resistance risks:
- Only use Doxy-PEP when prescribed by a healthcare provider
- Don’t share medications or use leftover antibiotics from other treatments
- Take the medication exactly as prescribed
- Continue regular STI testing to monitor for any resistant infections
- Use Doxy-PEP as part of a broader prevention strategy, not as the only method
Your healthcare provider will discuss these considerations with you and help weigh the benefits of STI prevention against potential risks.
What we know
- Overuse of antibiotics can lead to resistant bacterial strains
- Gonorrhoea already shows significant resistance to many antibiotics
- The impact of widespread Doxy-PEP use on resistance patterns is still being studied
- Responsible use and monitoring are essential
When to consider Doxy-PEP
Doxy-PEP may be considered during:
- Periods of high syphilis transmission in the community
- Attendance at sex-on-premises venues or events
- Travel periods involving casual sexual encounters
- Times when you’re having more frequent unprotected sex
- Periods when regular STI testing might be challenging
Learn about STIs
Take pride in your sexual health by knowing your STI status. There is no shame in testing and knowing what to look for, and can even help keep you and your sexual partners healthy.
Find out more about STIs, what to look for, how they’re spread, and what the treatment is by clicking on the STI below.
You are welcome at M Clinic
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If you are unsure if we are the right clinic for you, get in touch and we will be able to help you find the right fit for your needs.
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