Chlamydia Treatment
For non-pregnant adults, treat chlamydia with doxycycline 100 mg orally twice daily for 7 days as first-line therapy; azithromycin 1 g orally as a single dose is equally effective and preferred when adherence is uncertain. 1
First-Line Treatment Options
Both regimens demonstrate equivalent cure rates (97-98%) based on meta-analysis of randomized trials 1:
- Doxycycline 100 mg orally twice daily for 7 days - Less expensive, no higher adverse event risk
- Azithromycin 1 g orally as single dose - Enables directly observed therapy, better for populations with poor follow-up
Choose azithromycin when:
- Compliance with 7-day regimen is questionable
- Patient has erratic healthcare-seeking behavior
- Direct observation of therapy is feasible
- Single-dose convenience outweighs cost considerations
Choose doxycycline when:
- Patient adherence is reliable
- Cost is a primary concern
- Standard clinical setting with good follow-up
Recent evidence confirms doxycycline as the preferred agent 2, 3, 4, though azithromycin remains appropriate for specific populations.
Alternative Regimens
When first-line options are contraindicated or not tolerated 1:
- Erythromycin base 500 mg orally four times daily for 7 days
- Erythromycin ethylsuccinate 800 mg orally four times daily for 7 days
- Ofloxacin 300 mg orally twice daily for 7 days
- Levofloxacin 500 mg orally once daily for 7 days
Caveat: Erythromycin has lower efficacy due to gastrointestinal side effects that reduce compliance. Fluoroquinolones are more expensive without dosing advantages.
Pregnancy-Specific Treatment
Doxycycline, ofloxacin, and levofloxacin are absolutely contraindicated in pregnancy. 1
Recommended for pregnant women:
- Azithromycin 1 g orally as single dose (safe and effective based on clinical experience)
- Amoxicillin 500 mg orally three times daily for 7 days
Alternative regimens if needed:
- Erythromycin base 500 mg orally four times daily for 7 days
- Erythromycin base 250 mg orally four times daily for 14 days
- Erythromycin ethylsuccinate 800 mg orally four times daily for 7 days
- Erythromycin ethylsuccinate 400 mg orally four times daily for 14 days
Critical: Erythromycin estolate is contraindicated in pregnancy due to hepatotoxicity risk. Test-of-cure (preferably by NAAT) 3 weeks after completing therapy is mandatory for all pregnant women to prevent maternal and neonatal complications 1.
Gonorrhea Co-infection
Presumptive treatment for chlamydia is appropriate for all patients with confirmed gonorrhea due to frequent co-infection 1. Treat with standard chlamydia regimen plus appropriate gonorrhea therapy (ceftriaxone).
Post-Treatment Instructions
Patients must abstain from sexual intercourse:
- For 7 days after single-dose azithromycin
- Until completion of 7-day regimens (doxycycline, amoxicillin)
- Until all sex partners complete treatment 1
Dispense medications on-site and directly observe the first dose to maximize compliance.
Follow-Up Testing
Test-of-cure is NOT recommended for non-pregnant patients treated with recommended regimens, unless 1:
- Therapeutic compliance is questionable
- Symptoms persist
- Reinfection is suspected
- Patient is pregnant (mandatory retest)
Do not test <3 weeks after treatment completion - may yield false-negative results from low organism burden or false-positive NAAT results from dead organisms.
Retest all women approximately 3 months after treatment regardless of cure, as repeat infections are common (from untreated partners or new infected partners) and confer elevated PID risk 1.
Special Populations
HIV-infected patients: Use identical treatment regimens as HIV-negative patients 1.
Partner management: Expedited partner therapy (patient-delivered medication) is cost-effective for heterosexual partners but not recommended for men who have sex with men due to high risk of coexisting infections including undiagnosed HIV 1.