What is the recommended treatment for Chlamydia?

Chlamydia Treatment

First-Line Treatment Recommendations

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 have equivalent efficacy of approximately 97-98%. 1, 2

Choosing Between First-Line Options

• Azithromycin 1 g single dose is preferred when:

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

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

  • Cost is a primary concern (doxycycline is significantly less expensive) 1, 2
  • Patient can reliably complete a 7-day course 2

• Both regimens have similar mild-to-moderate gastrointestinal side effects (17-20% of patients) 2, 3

Alternative Treatment Regimens

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

• Levofloxacin 500 mg orally once daily for 7 days 1
• 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 azithromycin or doxycycline, and gastrointestinal side effects frequently cause poor compliance, making it a less desirable choice 1, 2

Treatment During Pregnancy

Azithromycin 1 g orally as a single dose is the preferred treatment during pregnancy. 4

• Alternative option: Amoxicillin 500 mg orally three times daily for 7 days 2, 4
• Second-line alternative: Erythromycin base 500 mg orally four times daily for 7 days 5, 2, 4

Absolute contraindications in pregnancy: 4

• Doxycycline 5, 1, 4
• Ofloxacin 5, 1
• Levofloxacin 4

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

Pediatric Dosing

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

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

For children <45 kg: 1, 4

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

For infants 1-3 months with chlamydial pneumonia: 1, 4

• 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 1, 4

Critical Management Steps

Medication Administration

• Dispense medications on-site when possible and directly observe the first dose to maximize compliance 1, 2
• Administer with food or milk if gastric irritation occurs with doxycycline 6

Sexual Activity Restrictions

• Patients must abstain from ALL sexual intercourse for 7 days after initiating treatment 1, 4
• Continue abstinence until ALL sex partners have completed treatment 1, 2, 4

Partner Management

• All sex partners from the preceding 60 days must be evaluated, tested, and empirically treated 1, 2, 4
• If last sexual contact was >60 days before diagnosis, still treat the most recent partner 1, 2
• Failing to treat partners leads to reinfection in up to 20% of cases 1
• Consider expedited partner therapy if partners are unlikely to seek care 4

Additional STI Testing

• Test all patients for gonorrhea, syphilis, and HIV at the initial visit 1
• If gonorrhea is confirmed, always treat chlamydia concurrently due to high coinfection rates 1, 2

Follow-Up and Retesting

Test-of-Cure (NOT Routinely Recommended)

• Do NOT perform test-of-cure for non-pregnant patients treated with recommended regimens 1, 2, 4
• Treatment failure rates are extremely low: 0-3% in males, 0-8% in females 5, 2, 4

Exceptions requiring test-of-cure 3-4 weeks after treatment: 1, 2

• Questionable therapeutic compliance
• Persistent symptoms
• Suspected reinfection
• Pregnancy (always required) 4

Critical timing: Never test before 3 weeks post-treatment—nucleic acid amplification tests yield false-positives from dead organisms 4

Reinfection Screening (STRONGLY RECOMMENDED)

• All women with chlamydia should be retested approximately 3 months after treatment, regardless of whether partners were reportedly treated 1, 2, 4
• Reinfection rates can reach 39% in some adolescent populations 5, 4
• Repeat infections carry elevated risk for pelvic inflammatory disease and complications compared to initial infection 1, 2, 4
• Men may also benefit from 3-month retesting, though evidence is more limited 1

Treatment of Recurrent Chlamydia

Most recurrent infections (84-92%) are reinfections from untreated or new partners, NOT treatment failures. 4

• Treat recurrent chlamydia with the same first-line regimens as initial infection 4
• High recurrence rates reflect partner reinfection and sexual network dynamics, not antibiotic resistance 4
• The single most important factor in preventing recurrence is treating all sexual partners 4

Special Consideration: Rectal Chlamydia

• For rectal chlamydia specifically, doxycycline 100 mg twice daily for 7 days is significantly more effective than azithromycin 7
• Pooled efficacy: doxycycline 99.6% vs. azithromycin 82.9% for rectal infections 7
• This represents a notable exception to the general equivalence of these two regimens 7

Common Pitfalls to Avoid

• Assuming treatment failure when reinfection is more likely—most recurrences are from untreated partners 4
• Testing too early after treatment—wait at least 3 weeks to avoid false-positives 4
• Not retesting women at 3 months—this is when reinfection risk and PID complications are highest 1, 4
• Allowing sexual activity before partner treatment is complete—both patient and all partners must complete treatment first 4
• Using non-culture tests (EIA, DFA) in children—these cause false-positives from cross-reaction with other organisms 1