How should I treat an 18‑year‑old male with uncomplicated urogenital Chlamydia trachomatis infection?

Treatment of Uncomplicated Chlamydia in an 18-Year-Old Male

Treat immediately with 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 first-line options. 1

First-Line Treatment Options

Azithromycin 1 g single oral dose is preferred when:

• Compliance is uncertain or follow-up unpredictable 1
• Directly observed therapy is desired 2, 1
• The patient has erratic health-care-seeking behavior 1

Doxycycline 100 mg orally twice daily for exactly 7 days is equally effective and offers:

• Lower cost than azithromycin 1
• Superior efficacy for rectal chlamydia (94% vs 85% cure rate) 1, 3
• Extensive clinical experience 1

Both regimens should be dispensed on-site when possible, with the first dose directly observed to maximize compliance. 2, 1

Mandatory Sexual Abstinence and Partner Management

• The patient must abstain from all sexual intercourse for 7 days after initiating treatment and until all symptoms have resolved 1, 3
• All sex partners from the preceding 60 days must be evaluated, tested, and treated empirically with the same regimen, even if asymptomatic 1, 3
• Partners should receive treatment without waiting for their own test results because sex partners of infected patients have substantially increased risk 1

Concurrent Gonorrhea Testing and Treatment

• Test for gonorrhea via NAAT at the initial visit 1
• If gonorrhea is confirmed or prevalence exceeds 5% in your population, treat concurrently with ceftriaxone 250 mg IM single dose PLUS azithromycin 1 g orally single dose 1, 3
• Coinfection rates range from 20-40% in high-prevalence populations 1, 3

Additional STI Screening

All patients diagnosed with chlamydia should be tested for:

• Syphilis 1
• HIV 2, 1

Follow-Up Recommendations

Test-of-cure is NOT recommended for asymptomatic men treated with recommended regimens because cure rates exceed 97%. 1 Testing before 3 weeks may yield false-positive results from residual DNA. 1

Repeat testing at 3 months is strongly recommended to detect reinfection, which occurs in up to 39% of cases and carries elevated risk for complications. 1 This should be done regardless of whether partners were reportedly treated. 1

Alternative Regimens (Only if First-Line Agents Cannot Be Used)

If azithromycin and doxycycline are contraindicated:

• Erythromycin base 500 mg orally four times daily for 7 days 2, 1
• Erythromycin ethylsuccinate 800 mg orally four times daily for 7 days 2, 1
• Ofloxacin 300 mg orally twice daily for 7 days 2, 1
• Levofloxacin 500 mg orally once daily for 7 days (88-94% cure rate vs 97-98% for first-line agents) 1

Note: Erythromycin has poor compliance due to gastrointestinal side effects and is less efficacious than first-line agents. 1 Fluoroquinolones offer no compliance advantage over doxycycline, are more expensive, and have inferior evidence. 1

Management of Persistent or Recurrent Symptoms

Do NOT retreat based on symptoms alone—require objective evidence of urethral inflammation (≥5 WBC per high-power field on urethral Gram stain or ≥10 WBC per high-power field on first-void urine microscopy). 1

If symptoms persist after completing therapy:

• Consider testing for Mycoplasma genitalium using NAAT on first-void urine or urethral swab 4
• M. genitalium responds poorly to doxycycline (30-40% cure rate) but better to azithromycin (85-95% for susceptible strains) 4
• For macrolide-resistant M. genitalium, use moxifloxacin 400 mg orally once daily for 7 days 4

Critical Pitfalls to Avoid

• Do NOT wait for test results before treating in high-risk populations with uncertain follow-up 1
• Do NOT assume partners were treated—directly verify or use expedited partner therapy 1
• Do NOT perform test-of-cure in asymptomatic patients treated with recommended regimens, as this wastes resources 1
• Do NOT use fluoroquinolones or tetracyclines in pregnancy—these are absolutely contraindicated 1, 3