Treatment of Chlamydia and Gonorrhea
Chlamydia Treatment
For uncomplicated genital chlamydia, treat with doxycycline 100 mg orally twice daily for 7 days as first-line therapy, which achieves 98% cure rates and is equally effective as azithromycin but superior for rectal infections. 1, 2, 3
First-Line Options for Genital Chlamydia
- Doxycycline 100 mg orally twice daily for 7 days is the preferred regimen due to 98% efficacy, lower cost, and extensive clinical experience 1, 2, 3
- Azithromycin 1 g orally as a single dose achieves 97% cure rates and should be reserved for situations where compliance with multi-day regimens is questionable, as it allows for directly observed therapy 1, 2, 3
Critical caveat for rectal chlamydia in men who have sex with men: Doxycycline is significantly superior to azithromycin for rectal infections, with 96.9% cure rate versus 76.4% for azithromycin (adjusted risk difference 19.9 percentage points, P<0.001) 4. A retrospective cohort also found azithromycin-treated men had 5.2 times higher risk of persistent/recurrent rectal infection at 14-90 days compared to doxycycline 5. Always use doxycycline for rectal chlamydia.
Alternative Regimens
When first-line options cannot be used: 1, 2
- Levofloxacin 500 mg orally once daily for 7 days
- Ofloxacin 300 mg orally twice daily for 7 days
- Erythromycin base 500 mg orally four times daily for 7 days (less desirable due to gastrointestinal side effects causing poor compliance) 3, 6
- Erythromycin ethylsuccinate 800 mg orally four times daily for 7 days 1, 6
Pregnancy Considerations
Doxycycline and fluoroquinolones are absolutely contraindicated in pregnancy. 1, 2
Recommended options during pregnancy: 1, 2, 6
- Azithromycin 1 g orally as a single dose (preferred)
- Amoxicillin 500 mg orally three times daily for 7 days
- Erythromycin base 500 mg orally four times daily for 7 days (if azithromycin cannot be used) 2, 6
Pregnant women require test-of-cure 3-4 weeks after treatment completion due to use of alternative regimens with lower efficacy. 2
Gonorrhea Treatment
For uncomplicated gonorrhea at all anatomic sites, treat with ceftriaxone 500 mg intramuscularly as a single dose, which is the current CDC-recommended first-line therapy. 1
First-Line Regimen
- Ceftriaxone 500 mg IM as a single dose for all uncomplicated urogenital, anorectal, and pharyngeal gonococcal infections 1
- Note: Older guidelines recommended ceftriaxone 125 mg IM, but current recommendations have increased to 500 mg due to emerging resistance 7, 1
Alternative Regimens (When Cephalosporins Cannot Be Used)
For patients with cephalosporin allergy: 7
- Spectinomycin 2 g IM as a single dose (98.2% cure rate for urogenital/anorectal infections, but only 52% effective for pharyngeal infections)
- Single-dose fluoroquinolones (ciprofloxacin 500 mg, ofloxacin 400 mg, or levofloxacin 250 mg orally) only if local resistance patterns permit 7
Critical warning: Fluoroquinolone resistance in gonorrhea is widespread in many regions, making these alternatives unreliable in most clinical settings 7, 8
Pharyngeal Gonorrhea Considerations
Pharyngeal gonococcal infections are more difficult to eradicate than urogenital/anorectal sites, requiring regimens with >90% cure rates. 7
- Ceftriaxone 500 mg IM remains first-line 1
- Ciprofloxacin 500 mg orally can be used only if resistance is not a concern 7
- Spectinomycin is unreliable (only 52% effective) for pharyngeal infections and should be avoided 7
Dual Therapy for Chlamydia-Gonorrhea Coinfection
When treating gonorrhea, always provide concurrent treatment for chlamydia if chlamydial infection has not been excluded, as coinfection rates range from 20-40%. 1, 2
Recommended approach: 1
- Ceftriaxone 500 mg IM for gonorrhea
- PLUS doxycycline 100 mg orally twice daily for 7 days (or azithromycin 1 g orally as single dose if compliance is a concern)
Routine dual therapy without testing for chlamydia is cost-effective when coinfection rates are high. 1
Implementation and Patient Management
Medication Dispensing and Compliance
- Dispense medications on-site when possible, with the first dose directly observed to maximize compliance 1, 2
- This is particularly important for azithromycin single-dose therapy 2
Sexual Activity Restrictions
Patients must abstain from all sexual intercourse for 7 days after initiating treatment (or until completion of 7-day regimens) and until all sex partners are treated. 1, 2
Partner Management
All sex partners from the previous 60 days must be evaluated, tested, and empirically treated for both gonorrhea and chlamydia. 1, 2
- If last sexual contact was >60 days before diagnosis, treat the most recent partner 2
- Failure to treat partners leads to reinfection in up to 20% of cases 2
Follow-Up and Test-of-Cure
Test-of-cure is NOT routinely recommended for non-pregnant patients treated with recommended regimens, as cure rates are 97-98%. 2, 3
Exceptions requiring test-of-cure at 3-4 weeks post-treatment: 2
- Questionable therapeutic compliance
- Persistent symptoms
- Suspected reinfection
- Pregnancy (always required)
Important: Testing before 3 weeks post-treatment is unreliable due to false-positive results from dead organisms detected by nucleic acid amplification tests. 2
Reinfection Screening
All women with chlamydia should be retested approximately 3 months after treatment to screen for reinfection, regardless of whether partners were reportedly treated. 2, 3
- Reinfection rates can reach 39% in some adolescent populations 2
- Repeat infections carry elevated risk for pelvic inflammatory disease and complications compared to initial infection 2
- Men may also benefit from retesting at 3 months, though evidence is more limited 2
Additional STI Testing
Patients diagnosed with chlamydia or gonorrhea should be tested for syphilis and HIV at the initial visit. 2
Special Populations
Pediatric Dosing for Chlamydia
For children ≥8 years weighing >45 kg: 2
- Azithromycin 1 g orally as single dose OR
- Doxycycline 100 mg orally twice daily for 7 days
For children <45 kg: 2
- Erythromycin base or ethylsuccinate 50 mg/kg/day orally divided into four doses daily for 14 days
For infants with chlamydial pneumonia (1-3 months): 2, 6
- Erythromycin base or ethylsuccinate 50 mg/kg/day orally divided into four doses daily for 14 days (approximately 80% effective; second course may be needed)
Avoid non-culture tests (EIA, DFA) in children due to false-positive results from cross-reaction with other organisms. 2
HIV-Positive Patients
Patients with HIV should receive the same treatment regimens as HIV-negative patients for both chlamydia and gonorrhea. 3