What is the recommended treatment for a patient with chlamydia (Chlamydia trachomatis)?

Treatment for Chlamydia (Chlamydia trachomatis)

For uncomplicated 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 achieve 97-98% cure rates and are equally effective. 1, 2, 3

First-Line Treatment Selection

Choose between two equally effective options based on patient-specific factors:

Azithromycin 1 g orally, single dose 1, 2, 3

• Preferred when:
  • Compliance with multi-day regimens is questionable 1, 2
  • Follow-up is unpredictable 1
  • Directly observed therapy is needed 1, 3
  • Treating young adults or populations with erratic health-care-seeking behavior 1
• Advantages: Single-dose therapy eliminates compliance concerns, can be dispensed and observed on-site 1, 2
• Cure rate: 97% 1, 3

Doxycycline 100 mg orally twice daily for 7 days 1, 2, 3

• Preferred when:
  • Cost is a primary concern (significantly less expensive than azithromycin) 1, 3
  • Patient can reliably complete a 7-day course 3
• Advantages: Lower cost, extensive clinical experience over longer period 1
• Cure rate: 98% 1, 3

Critical implementation: Dispense medications on-site when possible and directly observe the first dose to maximize compliance. 1, 2, 3

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

Use these only when azithromycin and doxycycline are contraindicated or not tolerated: 1, 2, 3

• Levofloxacin 500 mg orally once daily for 7 days 1, 2, 3
• Ofloxacin 300 mg orally twice daily for 7 days 1, 2, 3
• Erythromycin base 500 mg orally four times daily for 7 days 1, 2, 4
• Erythromycin ethylsuccinate 800 mg orally four times daily for 7 days 1, 2

Important caveat: Erythromycin is less efficacious than azithromycin or doxycycline and causes frequent gastrointestinal side effects leading to poor compliance—avoid unless absolutely necessary. 1, 2, 3

Treatment During Pregnancy

Azithromycin 1 g orally as a single dose is the preferred treatment during pregnancy. 1, 3

Alternative options for pregnant patients: 1, 3

• Amoxicillin 500 mg orally three times daily for 7 days 1, 2, 3
• Erythromycin base 500 mg orally four times daily for 7 days (if azithromycin cannot be tolerated) 1, 3, 4

Absolute contraindications in pregnancy: 1, 3

• Doxycycline 1, 3
• Ofloxacin 1, 3
• Levofloxacin 1, 3
• All fluoroquinolones 1, 3
• Erythromycin estolate (causes drug-related hepatotoxicity) 1

Mandatory follow-up: Pregnant women must undergo test-of-cure 3-4 weeks after treatment completion due to potential maternal and neonatal complications. 3

Pediatric Dosing

Children ≥8 years weighing >45 kg: 1, 3

• Azithromycin 1 g orally as a single dose, OR
• Doxycycline 100 mg orally twice daily for 7 days

Children <45 kg: 1, 3

• Erythromycin base or ethylsuccinate 50 mg/kg/day orally divided into four doses daily for 14 days

Neonates with chlamydial conjunctivitis or pneumonia (ages 1-3 months): 1, 4

• Erythromycin base or ethylsuccinate 50 mg/kg/day orally divided into four doses daily for 14 days
• Effectiveness approximately 80%; may require a second course 1

Critical Management Steps

Sexual activity restrictions: 1

• Patients must abstain from all sexual intercourse for 7 days after initiating treatment (regardless of regimen) 1
• Continue abstinence until all sex partners have completed treatment 1, 3

Partner management: 1, 3

• All sex partners from the preceding 60 days must be evaluated, tested, and empirically treated 1, 3
• Treat the most recent partner even if last sexual contact was >60 days before diagnosis 1
• Failing to treat sex partners leads to reinfection in up to 20% of cases 1

Additional STI testing at initial visit: 1

• Test for gonorrhea, syphilis, and HIV 1
• If gonorrhea is confirmed or prevalence is high, treat for both infections concurrently with ceftriaxone 250 mg IM single dose plus azithromycin 1 g orally single dose 1

Follow-Up and Retesting

Test-of-cure is NOT recommended for: 1, 2, 3

• Non-pregnant patients treated with recommended regimens (azithromycin or doxycycline) who are asymptomatic 1, 3
• Treatment failure rates are extremely low: 0-3% in males, 0-8% in females 2, 3

Test-of-cure IS indicated when: 1, 3

• Therapeutic compliance is questionable 1
• Symptoms persist after treatment 1
• Reinfection is suspected 1
• Patient is pregnant (mandatory) 3

Timing: Wait at least 3 weeks after treatment completion before testing, as nucleic acid amplification tests performed earlier can yield false-positive results from dead organisms. 1

Reinfection screening (distinct from test-of-cure): 1, 3

• All women with chlamydia should be retested approximately 3 months after treatment, regardless of whether partners were reportedly treated 1, 3
• Reinfection rates can reach 39% in some adolescent populations 3
• Repeat infections carry elevated risk for pelvic inflammatory disease and other complications compared to initial infection 1
• Men may also benefit from retesting at approximately 3 months, though evidence is more limited 1

Common Pitfalls to Avoid

• Do not use erythromycin as first-line treatment—gastrointestinal side effects cause poor compliance 1, 2
• Do not use non-culture tests (EIA, DFA) in children—risk of false-positive results from cross-reaction with other organisms 1
• Do not perform test-of-cure before 3 weeks post-treatment—nucleic acid amplification tests can detect DNA from dead organisms, not active infection 1
• Do not assume partners were treated—directly verify or use expedited partner therapy strategies 1
• Do not wait for test results if compliance with return visit is uncertain in high-prevalence populations—treat presumptively 1