What is the recommended treatment for a patient diagnosed with Chlamydia?

Chlamydia Treatment

For uncomplicated chlamydial infection 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 the two first-line options based on these specific factors:

Select azithromycin 1 g single dose when: 1, 2, 3

• Compliance with a 7-day regimen is questionable
• The patient has erratic health-care-seeking behavior
• Follow-up is unpredictable
• Directly observed therapy is needed
• Single-dose convenience outweighs cost considerations

Select doxycycline 100 mg twice daily for 7 days when: 2, 3, 4

• Cost is a primary concern (doxycycline is significantly less expensive)
• The patient can reliably complete a 7-day course
• Extensive clinical experience is preferred

Critical Management Steps

Medication dispensing and observation: 1, 2, 3

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

Sexual abstinence requirements: 1, 2, 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 (mandatory): 1, 2, 3

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

Alternative Treatment Regimens

Use these alternatives only when first-line options cannot be used: 1, 2, 3

• 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
• Erythromycin ethylsuccinate 800 mg orally four times daily for 7 days

Important caveat: Erythromycin is less efficacious than azithromycin or doxycycline and causes frequent gastrointestinal side effects that reduce compliance, making it the least desirable alternative. 1, 2

Treatment During Pregnancy

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

Alternative options for pregnant women: 1, 2, 3, 5

• Amoxicillin 500 mg orally three times daily for 7 days
• Erythromycin base 500 mg orally four times daily for 7 days

Absolute contraindications in pregnancy: 1, 2, 3

• Doxycycline
• Ofloxacin
• Levofloxacin
• All fluoroquinolones

Critical difference for pregnant patients: Test-of-cure is mandatory 3-4 weeks after treatment completion due to potential maternal and neonatal complications. 3

Pediatric Dosing

For children ≥8 years weighing >45 kg: 1, 2, 3, 4

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

For children <45 kg: 1, 2, 3, 5

• 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, 5

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

Follow-Up and Retesting

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. 2, 3

Test-of-cure IS indicated when: 1, 2, 3

• Therapeutic compliance is questionable
• Symptoms persist
• Reinfection is suspected
• The patient is pregnant (mandatory)

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

Reinfection screening (distinct from test-of-cure): 1, 2, 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
• Repeat infections carry elevated risk for pelvic inflammatory disease and complications compared to initial infection

Additional STI Testing

At the initial visit, test all patients diagnosed with chlamydia for: 1

• Gonorrhea (coinfection is common; if gonorrhea is confirmed, always treat chlamydia concurrently)
• Syphilis
• HIV

Common Pitfalls to Avoid

Reinfection prevention: Up to 20% of patients become reinfected when partners are not treated. 1 Verify that all partners from the last 60 days were adequately treated, even if the patient reports partner treatment.

Testing too early: Do not perform confirmation tests before 3 weeks post-treatment, as nucleic acid amplification tests can detect DNA from dead organisms, not active infection. 3

Presumptive treatment: In high-prevalence populations where compliance with return visits is uncertain, treat presumptively rather than waiting for test results. 1

Pregnancy considerations: Never use doxycycline or fluoroquinolones in pregnant women, and always perform test-of-cure in this population. 1, 3