Doxycycline Coverage and Dosing for Bacterial Infections

Antimicrobial Coverage

The Centers for Disease Control and Prevention recommends doxycycline as a first-line treatment for Chlamydia trachomatis, and as an alternative treatment for syphilis in non-pregnant patients with penicillin allergy, and it is effective against many strains of Neisseria gonorrhoeae in the United States, though not recommended as first-line due to increasing resistance 1

The American Academy of Pediatrics recommends pediatric dosing of doxycycline for children over 8 years old, with a dosage of 2 mg/lb (4.4 mg/kg) divided into two doses on the first day, and 1 mg/lb (2.2 mg/kg) daily thereafter, for children over 100 lbs, use adult dosing 2

The Centers for Disease Control and Prevention recommends doxycycline for the treatment of sexually transmitted infections, including Chlamydia, with a dosage of 100 mg orally twice daily for 7 days 3, 4
The Infectious Diseases Society of America recommends doxycycline for the treatment of skin and soft tissue infections, including purulent cellulitis and MRSA skin infections, with a dosage of 100 mg orally twice daily 2

The Centers for Disease Control and Prevention reports that doxycycline has common adverse effects, including photosensitivity, gastrointestinal symptoms, and esophageal erosion and ulceration, and it is contraindicated in pregnancy and children under 8 years of age 1, 2

The Centers for Disease Control and Prevention suggests the use of doxycycline as post-exposure prophylaxis for high-risk populations, with a dosage of 200 mg within 72 hours after sexual contact 3, 5

The Centers for Disease Control and Prevention (CDC) recommends a 200mg dose of doxycycline for post-exposure prophylaxis (doxy PEP) to be taken within 72 hours after sexual exposure, with a maximum of 200mg every 24 hours, for individuals who have had oral, vaginal, or anal sex 6, 7
A 200mg post-exposure prophylaxis regimen has demonstrated significant reductions in bacterial STI acquisition, including chlamydia, syphilis, and gonorrhea, in three large randomized controlled trials among men who have sex with men (MSM) and transgender women (TGW) 6, 7, 8

Daily 100mg doxycycline as pre-exposure prophylaxis (PrEP) showed a 73% reduction in bacterial STI incidence at 48 weeks in a 2015 trial, with demonstrated decreases in chlamydia and syphilis, according to the CDC guidelines 6, 7, 8
The current CDC guidelines focus on post-exposure prophylaxis (doxy PEP) at 200mg, not daily pre-exposure prophylaxis, as the recommended prevention strategy for chlamydia prevention 6, 7

For treatment of established chlamydia infection, the standard regimen is doxycycline 100mg orally twice daily for 7 days, according to the CDC and other medical guidelines 9, 10, 11

Doxy PEP is specifically recommended for men who have sex with men (MSM) and transgender women (TGW) who have had a bacterial STI diagnosed in the past 12 months, and should be implemented within a comprehensive sexual health approach including STI screening at baseline and every 3-6 months, as recommended by the CDC 6, 7, 8