Treatment of Chlamydia

First-Line Treatment Options

For uncomplicated genital chlamydia in non-pregnant adults, use 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

Choosing Between First-Line Options

Azithromycin 1 g single dose is preferred when:
- Compliance is questionable or follow-up is unpredictable 1, 2
- Directly observed therapy is needed 1, 2
- Patient has erratic health-care-seeking behavior 1
- Single-visit treatment is desired 1
Doxycycline 100 mg twice daily for 7 days is preferred when:
- Cost is a primary concern (doxycycline is less expensive) 1, 2
- Patient can reliably complete 7-day regimen 1
- Treating rectal chlamydia (see below) 3

Critical Implementation Details

Dispense medications on-site when possible and directly observe the first dose to maximize compliance 1, 2
Patients must abstain from all sexual intercourse for 7 days after initiating treatment AND until all sex partners have been treated 1, 2
If gastric irritation occurs with doxycycline, give with food or milk (absorption is not significantly affected) 4

Alternative Treatment Regimens

Use these alternatives only when first-line options cannot be used: 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
Ofloxacin 300 mg orally twice daily for 7 days 1, 2
Levofloxacin 500 mg orally once daily for 7 days 1, 2

Important Caveat About Erythromycin

Erythromycin is less efficacious than azithromycin or doxycycline 2
Gastrointestinal side effects frequently lead to poor compliance 1, 2
Should not be used as first-line treatment 1

Treatment During Pregnancy

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

Pregnancy-Specific Regimens

First-line: Azithromycin 1 g orally single dose 1
Alternative: Amoxicillin 500 mg orally three times daily for 7 days 1, 2
Second alternative: Erythromycin base 500 mg orally four times daily for 7 days 1

Absolute Contraindications in Pregnancy

Doxycycline is absolutely contraindicated in pregnancy 1, 4
Ofloxacin is contraindicated in pregnancy 1

Special Pregnancy Considerations

Pregnant women should ALWAYS undergo test-of-cure 3-4 weeks after treatment completion (preferably by culture) due to use of alternative regimens with lower efficacy 1

Pediatric Treatment

Children ≥8 Years Weighing >45 kg

Azithromycin 1 g orally single dose OR doxycycline 100 mg orally twice daily for 7 days 5, 1

Children <45 kg

Erythromycin base or ethylsuccinate 50 mg/kg/day orally divided into 4 doses daily for 14 days 5, 1

Infants with Chlamydial Pneumonia (Ages 1-3 Months)

Erythromycin base or ethylsuccinate 50 mg/kg/day orally divided into 4 doses daily for 14 days 5, 1
Treatment effectiveness is approximately 80%; a second course may be required 5, 1
Follow-up is recommended to determine whether pneumonia has resolved 5

Critical Pediatric Testing Caveat

Do NOT use non-culture tests (EIA, DFA) in children due to false-positive results from cross-reaction with other organisms 1

Special Situation: Rectal Chlamydia

For rectal chlamydia, doxycycline 100 mg orally twice daily for 7 days is strongly preferred over azithromycin. 3

Doxycycline achieves 99.6% efficacy for rectal chlamydia 3
Azithromycin achieves only 82.9% efficacy for rectal chlamydia 3
The efficacy difference is 19.9% in favor of doxycycline 3

Partner Management

All sex partners from the previous 60 days must be evaluated, tested, and empirically treated. 1, 2

If last sexual contact was >60 days before diagnosis, the most recent partner should still be treated 1, 2
Failing to treat sex partners leads to reinfection in up to 20% of cases 1
Partners should receive the same treatment regimens as the index patient 1

Follow-Up and Retesting

Test-of-Cure (NOT Routinely Recommended)

Do NOT perform test-of-cure for non-pregnant patients treated with recommended regimens (azithromycin or doxycycline have 97-98% cure rates) 1, 2
Test-of-cure should ONLY be performed if: 1, 2
- Therapeutic compliance is questionable
- Symptoms persist
- Reinfection is suspected

Critical Timing Issue

Testing before 3 weeks post-treatment is unreliable because nucleic acid amplification tests can yield false-positive results from dead organisms 1
If test-of-cure is indicated, perform it 3-4 weeks after treatment completion 1

Reinfection Screening (STRONGLY RECOMMENDED)

All women with chlamydia should be retested approximately 3 months after treatment to screen for reinfection, regardless of whether partners were reportedly treated. 1, 2

Reinfection rates can reach up to 39% in some adolescent populations 1
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

Coinfection Considerations

Gonorrhea Coinfection

If gonorrhea is confirmed, always treat chlamydia concurrently due to high coinfection rates 1
Patients with gonorrhea should receive presumptive treatment for chlamydia 1

Additional STI Testing

Patients diagnosed with chlamydia should be tested for gonorrhea, syphilis, and HIV at the initial visit 1

Common Pitfalls to Avoid

Do NOT use erythromycin as first-line treatment—it has lower efficacy and poor compliance due to gastrointestinal side effects 1, 2
Do NOT use azithromycin for rectal chlamydia—doxycycline is significantly more effective 3
Do NOT forget to treat sex partners—this leads to reinfection in up to 20% of cases 1
Do NOT use doxycycline in pregnancy—it is absolutely contraindicated 1, 4
Do NOT perform test-of-cure before 3 weeks—false-positives from dead organisms will occur 1
Do NOT skip 3-month reinfection screening in women—reinfection rates are very high 1, 2

What is the recommended treatment for chlamydia?

Help us tailor your experience