What is the recommended treatment for chlamydia?

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 with approximately 97-98% efficacy. 1, 2

First-Line Treatment Options

Choose azithromycin when compliance is uncertain; choose doxycycline when cost is a concern.

• Azithromycin 1 g orally as a single dose is preferred in populations with erratic healthcare-seeking behavior, young adults, or when directly observed therapy is needed 1, 2

  • Microbial cure rate: approximately 97% 2, 3
  • Can be administered on-site with directly observed first dose to eliminate compliance concerns 1, 2
  • More cost-effective when follow-up is unpredictable 1

• Doxycycline 100 mg orally twice daily for 7 days is equally effective with lower cost 1, 2, 4

  • Microbial cure rate: approximately 98% 2, 3
  • Extensive clinical experience over longer period 1
  • Critical caveat: Doxycycline is absolutely contraindicated in pregnancy 1

• Meta-analyses confirm equal efficacy between azithromycin and doxycycline for genital chlamydial infections, with similar rates of mild-to-moderate gastrointestinal side effects 2, 3

Alternative Treatment Regimens

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

• Erythromycin base 500 mg orally four times daily for 7 days 1, 2, 5
• 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 limitation: Erythromycin is less efficacious than azithromycin or doxycycline, with gastrointestinal side effects frequently causing poor compliance. 1, 2

Treatment During Pregnancy

Azithromycin 1 g orally as a single dose is the preferred treatment during pregnancy. 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, 2
• Doxycycline and ofloxacin are absolutely contraindicated during pregnancy 1
• Pregnant women must always undergo test-of-cure, preferably by culture, due to use of alternative regimens with lower efficacy 1

Pediatric Dosing

• Children ≥8 years weighing >45 kg: Azithromycin 1 g orally as a single dose OR doxycycline 100 mg orally twice daily for 7 days 1, 4
• Children <45 kg: Erythromycin base or ethylsuccinate 50 mg/kg/day orally divided into four doses daily for 14 days 1
• Infants with chlamydial pneumonia (1-3 months): Erythromycin base or ethylsuccinate 50 mg/kg/day orally divided into four doses daily for 14 days, with approximately 80% effectiveness and possible need for second course 1

Critical Implementation Steps

Maximize treatment success by following these protocols:

• Dispense medications on-site when possible with directly observed first dose 1, 2
• Patients must abstain from all sexual intercourse for 7 days after initiating treatment and until all sex partners are treated 1
• Administer doxycycline with adequate fluids to reduce risk of esophageal irritation and ulceration 4
• If gastric irritation occurs with doxycycline, give with food or milk (absorption not significantly affected) 4

Partner Management

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

• If 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

Concurrent STI Testing and Treatment

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

Follow-Up Recommendations

Test-of-cure is NOT recommended for non-pregnant patients treated with recommended regimens (azithromycin or doxycycline) due to high cure rates of 97-98%. 1

• Exceptions requiring test-of-cure at 3-4 weeks post-treatment: 1

  • Questionable therapeutic compliance
  • Persistent symptoms
  • Suspected reinfection
  • All pregnant women (mandatory)

• Testing before 3 weeks post-treatment is unreliable because nucleic acid amplification tests yield false-positive results from dead organisms 1

Reinfection Screening (Distinct from Test-of-Cure)

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

• Repeat infections carry elevated risk for pelvic inflammatory disease and complications compared to initial infection 1
• Reinfection rates can reach up to 39% in some adolescent populations 1
• Men may also benefit from retesting at approximately 3 months, though evidence is more limited 1

Special Consideration: Rectal Chlamydia

• For rectal chlamydia, doxycycline 100 mg orally twice daily for 7 days is strongly preferred over azithromycin 6
• Azithromycin efficacy for rectal chlamydia is only 82.9% compared to 99.6% for doxycycline 6
• The efficacy difference of 19.9% in favor of doxycycline is clinically significant 6

Common Pitfalls to Avoid

• Not dispensing medication on-site or observing first dose in high-risk populations 1, 2
• Failing to counsel patients on 7-day sexual abstinence and partner treatment 1
• Using erythromycin without recognizing poor compliance due to gastrointestinal side effects 1, 2
• Prescribing doxycycline to pregnant patients 1
• Performing test-of-cure before 3 weeks post-treatment (yields false-positives) 1
• Not retesting women at 3 months for reinfection screening 1, 2