Doxycycline Treatment Guidelines

Antimicrobial Coverage and Uses

The American College of Physicians recommends doxycycline as a first-line treatment for Chlamydia trachomatis infections 1
The CDC recommends doxycycline as an alternative treatment for syphilis in non-pregnant patients with penicillin allergy 1
Doxycycline is effective against many strains of Neisseria gonorrhoeae, though not recommended as first-line due to increasing resistance, as reported by the MMWR Recommendations and Reports 2

The CDC recommends doxycycline post-exposure prophylaxis (doxy PEP) for specific high-risk populations, including gay, bisexual, and other men who have sex with men (MSM) and transgender women (TGW) with a history of at least one bacterial STI in the past 12 months 3
The dosage for doxy PEP is 200 mg taken within 72 hours after sexual contact (not to exceed 200 mg per 24 hours), as recommended by the MMWR Recommendations and Reports 2 and Praxis Medical Insights: Practical Summaries of Clinical Guidelines 4
Doxy PEP reduces syphilis and chlamydia infections by >70% and gonococcal infections by approximately 50%, according to Praxis Medical Insights: Practical Summaries of Clinical Guidelines 4
The CDC recommends that doxy PEP be implemented alongside comprehensive sexual health approaches, including regular STI screening every 3-6 months 3

Doxycycline has a long elimination half-life of approximately 12 hours, allowing once or twice daily dosing, as reported by the MMWR Recommendations and Reports 2

The most common adverse effects of doxycycline include photosensitivity, gastrointestinal symptoms, and esophageal erosion and ulceration, according to the MMWR Recommendations and Reports 2
Most adverse effects resolve with discontinuation of the medication, as reported by the MMWR Recommendations and Reports 2

The CDC recommends that bacterial STI testing be performed at anatomic sites of exposure at baseline and every 3-6 months for patients on doxy PEP 3
Ongoing need for doxy PEP should be reassessed every 3-6 months, as recommended by the CDC 3
HIV screening should be performed for HIV-negative MSM and TGW according to current recommendations, as reported by the MMWR Recommendations and Reports 5