What is the recommended treatment for Chlamydia?

Recommended Treatment for Chlamydia

For uncomplicated genital chlamydia in non-pregnant adults, treat with either azithromycin 1 g orally as a single dose or doxycycline 100 mg orally twice daily for 7 days—both regimens achieve 97-98% cure rates and are equally effective. 1, 2, 3

First-Line Treatment Selection

Choose between the two first-line options based on these specific factors:

• Azithromycin 1 g single dose is preferred when:

  • Compliance with a 7-day regimen is questionable 1, 2
  • Follow-up is unpredictable or the patient has erratic health-care-seeking behavior 1, 2
  • Directly observed therapy is needed (can be administered on-site) 1, 3
  • Treating young adults or populations with poor adherence patterns 2

• Doxycycline 100 mg twice daily for 7 days is preferred when:

  • Cost is a primary concern (significantly less expensive than azithromycin) 2, 3
  • The patient can reliably complete a 7-day course 2
  • Treating rectal chlamydia (doxycycline shows 99.6% efficacy vs. 82.9% for azithromycin in rectal infections) 4

Meta-analyses confirm these two regimens have equivalent efficacy for genital infections, with similar rates of mild-to-moderate gastrointestinal side effects (17-20%). 3, 5

Treatment During Pregnancy

Azithromycin 1 g orally as a single dose is the preferred treatment during pregnancy. 1, 2

• Alternative options include amoxicillin 500 mg orally three times daily for 7 days or erythromycin base 500 mg orally four times daily for 7 days 2, 3
• Doxycycline, ofloxacin, and levofloxacin are absolute contraindications in pregnancy due to potential fetal harm 1, 2
• Pregnant women must undergo test-of-cure 3-4 weeks after treatment completion due to lower efficacy of alternative regimens 1

Alternative Regimens (When First-Line Options Cannot Be Used)

Use these only when azithromycin and doxycycline are contraindicated or unavailable: 2, 3

• Levofloxacin 500 mg orally once daily for 7 days 1, 2
• Ofloxacin 300 mg orally twice daily for 7 days 1, 2
• Erythromycin base 500 mg orally four times daily for 7 days 1, 2
• Erythromycin ethylsuccinate 800 mg orally four times daily for 7 days 1, 2

Important caveat: Erythromycin is less efficacious than first-line options and causes frequent gastrointestinal side effects leading to poor compliance—avoid when possible. 1, 3

Pediatric Dosing

• Children ≥8 years weighing >45 kg: Azithromycin 1 g orally single dose OR doxycycline 100 mg orally twice daily for 7 days 1, 2
• Children <45 kg: Erythromycin base or ethylsuccinate 50 mg/kg/day orally divided into four doses daily for 14 days 1, 2
• Infants 1-3 months with chlamydial pneumonia: 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) 1

Critical Management Steps

Medication administration and compliance optimization:

• Dispense medications on-site when possible and directly observe the first dose to maximize compliance 1, 2
• Administer doxycycline with adequate fluids to reduce esophageal irritation risk 6
• If gastric irritation occurs with doxycycline, give with food or milk (absorption not significantly affected) 6

Sexual activity restrictions:

• Patients must abstain from all sexual intercourse for 7 days after initiating treatment 1, 2
• Continue abstinence until all sex partners have completed treatment 1, 2

Partner management:

• All sex partners from the preceding 60 days must be evaluated, tested, and empirically treated 1, 2
• If last sexual contact was >60 days before diagnosis, still treat the most recent partner 1
• Failing to treat sex partners leads to reinfection in up to 20% of cases 1

Concurrent Testing and Treatment

• Test all chlamydia-positive patients for gonorrhea, syphilis, and HIV at the initial visit 1
• If gonorrhea is confirmed or prevalence is high, always treat presumptively for both infections due to substantial coinfection rates 1
• Treating chlamydia alone when gonorrhea is present leads to treatment failure 1

Follow-Up and Retesting

Test-of-cure (3-4 weeks post-treatment):

• NOT recommended for non-pregnant patients treated with recommended regimens, as treatment failure rates are extremely low (0-3% in males, 0-8% in females) 2, 3
• Only perform test-of-cure if: therapeutic compliance is questionable, symptoms persist, or reinfection is suspected 1, 3
• Testing before 3 weeks is unreliable due to false-positive results from dead organisms 1
• Mandatory for all pregnant women 3-4 weeks after treatment completion 2

Reinfection screening (3 months post-treatment):

• All women with chlamydia should be retested approximately 3 months after treatment, regardless of whether partners were reportedly treated 1, 2
• 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 1
• Men may also benefit from 3-month retesting, though evidence is more limited 1

Common Pitfalls to Avoid

• Do not wait for test results if compliance with return visit is uncertain in high-prevalence populations—treat presumptively 1
• Do not use non-culture tests (EIA, DFA) in children due to false-positive results from cross-reaction with other organisms 1
• Do not rely on azithromycin at recommended doses to treat syphilis—antimicrobial agents used for non-gonococcal urethritis may mask incubating syphilis 7
• Do not use azithromycin for rectal chlamydia when doxycycline is available—efficacy difference is approximately 20% in favor of doxycycline 4