What is the recommended antibiotic treatment for chlamydia?

Recommended Antibiotic 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 achieve approximately 97-98% cure rates and are equally effective. 1, 2, 3

First-Line Treatment Selection

Choose azithromycin 1 g single dose when:

• Compliance with a 7-day regimen is questionable 1, 2, 3
• Follow-up is unpredictable or patient has erratic health-care-seeking behavior 4, 1, 3
• Directly observed therapy is needed (particularly in adolescents and young adults) 1, 3
• Single-dose convenience outweighs cost considerations 4, 1

Choose doxycycline 100 mg twice daily for 7 days when:

• Cost is a primary concern, as doxycycline is significantly less expensive 2, 3
• Patient can reliably complete a 7-day course 3
• Extensive clinical experience is preferred 2

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

The following alternatives have lower efficacy or tolerability: 1, 3

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

Critical caveat: Erythromycin causes frequent gastrointestinal side effects that lead to poor compliance, making it less desirable than first-line options. 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 women:

• Amoxicillin 500 mg orally three times daily for 7 days 1, 2, 3
• Erythromycin base 500 mg orally four times daily for 7 days 1, 3

Absolute contraindications in pregnancy: Doxycycline, ofloxacin, and levofloxacin are contraindicated due to potential fetal harm. 1, 3

Mandatory follow-up: Pregnant women must undergo test-of-cure 3-4 weeks after treatment completion due to potential maternal and neonatal complications. 1, 3

Pediatric Dosing

For 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

For children <45 kg: 1, 3

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

For infants with chlamydial pneumonia (ages 1-3 months): 1

• Erythromycin base or ethylsuccinate 50 mg/kg/day orally divided into four doses daily for 14 days
• Treatment effectiveness is approximately 80%, and a second course may be needed 1

Critical Implementation Steps to Maximize Cure Rates

Medication dispensing: 1, 3

• Dispense medications on-site when possible
• Directly observe the first dose to maximize compliance

Sexual abstinence requirements: 1, 3

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

Partner management (essential to prevent reinfection): 1, 3

• All sex partners from the preceding 60 days must be evaluated, tested, and empirically treated
• Failing to treat sex partners leads to reinfection in up to 20% of cases 1

Follow-Up and Retesting Strategy

Test-of-cure is NOT recommended for non-pregnant patients treated with azithromycin or doxycycline because treatment failure rates are extremely low (0-3% in males, 0-8% in females). 1, 3

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

• Therapeutic compliance is questionable
• Symptoms persist after treatment
• Reinfection is suspected
• Testing before 3 weeks post-treatment is unreliable due to 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
• Reinfection rates can reach 39% in some adolescent populations 3
• Repeat infections carry elevated risk for pelvic inflammatory disease and complications compared to initial infection 1

Special Considerations

Coinfection with gonorrhea: 1

• Coinfection with gonorrhea is common among chlamydia patients
• If gonorrhea is confirmed, always treat chlamydia concurrently due to high coinfection rates

Rectal chlamydia in men who have sex with men: 5

• Recent high-quality evidence shows doxycycline 100 mg twice daily for 7 days is superior to azithromycin 1 g single dose for asymptomatic rectal chlamydia (96.9% vs 76.4% cure rate, P<0.001)
• For rectal chlamydia, strongly prefer doxycycline over azithromycin

Common pitfall to avoid: Do not wait for test results if compliance with return visit is uncertain in high-prevalence populations—treat presumptively. 1