Doxycycline is a tetracycline-class antibiotic that stops bacteria from multiplying and spreading.

Taking doxycycline within 24 to 72 hours after exposure allows the medicine to act before an infection becomes established.

DoxyPEP may be suitable for people at ongoing risk of bacterial STIs — for example, those with multiple partners or whose partners have recently tested positive.

You will complete a short online clinical assessment to confirm your suitability, medical history, and allergies before any prescription is issued.

When prescribed correctly and taken as directed, doxycycline is considered safe for most adults.

Common side effects may include:
• Mild nausea or upset stomach
• Increased sun sensitivity
• Diarrhoea or thrush

Serious side effects are rare. Stop taking the medication and seek medical advice if you experience rash, swelling, or yellowing of the skin or eyes.

According to BASHH guidance:

• Take 200 mg (2 tablets) as soon as possible after unprotected sex — ideally within 24 to 72 hours
• Then take 100 mg (1 tablet daily for 3 days)

Always follow the instructions on your pharmacy label and complete the course as prescribed.

No — doxycycline only helps prevent certain bacterial infections such as chlamydia and syphilis.

It does not protect against HIV, gonorrhoea, or viral STIs. You should continue to use condoms and attend regular STI screening for full protection.

Complete a secure online consultation form
A UK-registered clinician reviews your answers
If suitable, a private prescription is issued and dispensed by a GPhC-registered pharmacy
Your medication is delivered discreetly:

• Same-day delivery in London (orders before 11am)
• Next-day delivery across the UK (orders before 5pm)

We offer flexible pricing options:

Single purchase
£59.99 for 25 treatments
Includes clinical review, private prescription, and tracked delivery

Subscription plan
£44.50 every 6 weeks for 25 treatments
Includes ongoing clinical review, repeat prescriptions, and delivery

Annual plan (pre-paid)
£360 per year (9 packs of 25 treatments)
Equivalent to £40 per pack — offering a saving compared to single purchase

Includes prescriptions and delivery throughout the year

All options include clinician review and discreet tracked delivery. No hidden fees.

Some patients use DoxyPEP as part of an ongoing sexual health prevention plan.

Your prescriber will review your use regularly to ensure it remains safe and appropriate.

Stop taking doxycycline and seek medical advice if you experience:

• Severe rash or swelling
• Difficulty breathing
• Yellowing of the skin or eyes

For urgent concerns, call NHS 111 or dial 999 in an emergency.

Contact our clinical team here for confidential advice.