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

Chlamydia Treatment

For uncomplicated chlamydia 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 clinical factors:

Azithromycin 1 g single dose is preferred when:

• Compliance with a 7-day regimen is questionable 1, 2, 3
• Follow-up is unpredictable or unlikely 1, 3
• Directly observed therapy is needed 1, 2
• Treating young adults or populations with erratic health-care-seeking behavior 1, 3

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 3
• There is extensive clinical experience supporting its use 2

Alternative Regimens (Second-Line Only)

Use these alternatives only when first-line options cannot be used due to allergy or intolerance: 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, 3
• 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 that reduce compliance—making it the least desirable alternative. 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, 2, 3

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

Critical difference for pregnant patients: Test-of-cure is mandatory 3-4 weeks after treatment completion in pregnant women due to potential maternal and neonatal complications, unlike non-pregnant patients where it is not routinely recommended. 3

Pediatric Dosing

For children ≥8 years weighing >45 kg:

• Azithromycin 1 g orally as a single dose, OR 1, 3
• Doxycycline 100 mg orally twice daily for 7 days 1, 3, 4

For children <45 kg:

• Erythromycin base or ethylsuccinate 50 mg/kg/day orally divided into four doses daily for 14 days 1, 3

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

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

Critical Management Steps

Medication dispensing and compliance:

• Dispense medications on-site when possible 1, 2, 3
• Directly observe the first dose to maximize compliance 1, 2, 3

Sexual abstinence requirements:

• Patients must abstain from all sexual intercourse for 7 days after initiating treatment 1, 2, 3
• Continue abstinence until all sex partners have completed treatment 1, 2, 3

Partner management (critical to prevent reinfection):

• All sex partners from the preceding 60 days must be evaluated, tested, and empirically treated 1, 2, 3
• If the last sexual contact was >60 days before diagnosis, still treat the most recent partner 1, 2
• Failing to treat sex partners leads to reinfection in up to 20% of cases 1

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 only when:

• Therapeutic compliance is questionable 1, 2, 3
• Symptoms persist 1, 2, 3
• Reinfection is suspected 1, 2, 3
• Patient is pregnant (mandatory) 3

Timing caveat: Testing before 3 weeks post-treatment is unreliable because nucleic acid amplification tests can yield false-positive results from dead organisms that persist after successful treatment. 1, 3

Reinfection screening (distinct from test-of-cure):

• All women with chlamydia should be retested approximately 3 months after treatment, regardless of whether partners were reportedly treated. 1, 2, 3
• Reinfection rates can reach 39% in some adolescent populations 1, 3
• Repeat infections carry an 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

Additional Testing at Initial Visit

Patients diagnosed with chlamydia should be tested for:

• Gonorrhea (coinfection is common; treat presumptively if gonorrhea is confirmed) 1
• Syphilis 1
• HIV 1

Common Pitfalls to Avoid

• Do not use erythromycin as first-line treatment—gastrointestinal side effects frequently lead to poor compliance. 2, 3
• Do not perform test-of-cure before 3 weeks—false-positive results from dead organism DNA will occur. 1, 3
• Do not assume partner treatment occurred—retest at 3 months regardless of reported partner treatment. 1, 3
• Do not use non-culture tests (EIA, DFA) in children—risk of false-positive results from cross-reaction with other organisms. 1