Chlamydia Treatment Recommendations
The recommended first-line treatment for chlamydia infection is either azithromycin 1 g orally in a single dose or doxycycline 100 mg orally twice daily for 7 days, as recommended by the CDC. 1
First-Line Treatment Options
Azithromycin: 1 g orally in a single dose
- Advantages: Single-dose therapy improves compliance
- Particularly useful when compliance with multi-day regimens is a concern
- Can be dispensed on-site with directly observed therapy
Doxycycline: 100 mg orally twice daily for 7 days 1, 2
- Equally effective as azithromycin
- Lower cost option
- Should be taken with food or milk if gastric irritation occurs
Alternative Treatment Options
For patients who cannot take first-line treatments:
Fluoroquinolones:
- Ofloxacin 300 mg orally twice daily for 7 days
- Levofloxacin 500 mg orally once daily for 7 days
- Erythromycin base 500 mg orally four times daily for 7 days
- Erythromycin ethylsuccinate 800 mg orally four times daily for 7 days
- Note: Higher gastrointestinal side effect profile
Special Populations
Pregnant Patients
- First choice: Azithromycin 1 g orally in a single dose 1
- Alternatives:
- Amoxicillin 500 mg orally three times daily for 7-10 days
- Erythromycin base (dosing per guidelines)
Children
- Weight <45 kg: Erythromycin 50 mg/kg/day divided into four doses daily for 14 days 1
- Weight >45 kg but age <8 years: Azithromycin 1 g orally in a single dose
- Age >8 years: Either azithromycin 1 g single dose or doxycycline (if appropriate weight)
Clinical Considerations
Efficacy
Clinical studies have demonstrated comparable efficacy between azithromycin and doxycycline. A controlled trial showed that only 4% of patients treated with azithromycin and 2% of patients treated with doxycycline had treatment failures 4. This difference was not statistically significant.
Compliance Factors
- For patients with poor compliance history or unpredictable follow-up, azithromycin may be more appropriate despite higher cost 1
- To maximize compliance, medications should be dispensed on site and first dose directly observed
Side Effects
- Both medications have similar side effect profiles (primarily gastrointestinal)
- 17-19% of patients on azithromycin and 20-33% of patients on doxycycline experience mild to moderate side effects 5, 4
Partner Management and Follow-up
- All sexual partners from the previous 60 days should be evaluated, tested, and treated 1
- Patients should abstain from sexual intercourse for 7 days after single-dose therapy or until completion of multi-day regimen
- Routine test-of-cure is not recommended after treatment with azithromycin or doxycycline unless symptoms persist
- Consider rescreening 3-4 months after treatment due to high risk of reinfection
- Always test for other STIs, especially gonorrhea, which commonly co-occurs with chlamydial infections
Important Caveats
- Emerging research suggests potential concerns about azithromycin treatment failure for rectal chlamydia infections in men who have sex with men (MSM) 6
- Patients should be counseled about the importance of completing the full course of doxycycline if prescribed
- Doxycycline should be avoided in pregnancy and in children under 8 years of age
- When treating chlamydia, consider empiric treatment for gonorrhea if co-infection is suspected