What are the CDC (Centers for Disease Control and Prevention) recommended treatment regimens, abstinence period, expedited partner therapy, retesting schedule, and screening recommendations for chlamydia, gonorrhea, syphilis, trichomoniasis, and pelvic inflammatory disease?

CDC Treatment Guidelines for Common Sexually Transmitted Infections

Chlamydia

First-Line Treatment

Treat uncomplicated chlamydia with either azithromycin 1 g orally as a single dose or doxycycline 100 mg orally twice daily for 7 days, both achieving 97-98% cure rates. 1, 2

• Azithromycin 1 g single dose is preferred when compliance is uncertain, follow-up is unpredictable, or in populations with erratic health-care-seeking behavior 1, 2
• Doxycycline 100 mg twice daily for 7 days is preferred when cost is a concern, as it is significantly less expensive 2
• Medications should be dispensed on-site with the first dose directly observed to maximize compliance 1

Alternative Regimens

• Levofloxacin 500 mg orally once daily for 7 days 3, 1
• Ofloxacin 300 mg orally twice daily for 7 days 3
• Erythromycin base 500 mg orally four times daily for 7 days 3
• Erythromycin ethylsuccinate 800 mg orally four times daily for 7 days 3

Note: Erythromycin has frequent gastrointestinal side effects that discourage compliance and is less efficacious than first-line agents 3, 2

Pregnancy-Specific Treatment

Azithromycin 1 g orally as a single dose is the preferred treatment during pregnancy. 1, 2

• Alternative: Amoxicillin 500 mg orally three times daily for 7 days 3, 2
• Secondary alternatives: Erythromycin base 500 mg orally four times daily for 7 days OR erythromycin base 250 mg orally four times daily for 14 days 3
• Absolute contraindications in pregnancy: Doxycycline, ofloxacin, levofloxacin, and all fluoroquinolones 3, 2
• Erythromycin estolate is contraindicated due to drug-related hepatotoxicity 3
• Mandatory test-of-cure 3-4 weeks after treatment completion for all pregnant women, preferably by culture 3, 2

Pediatric Dosing

• Children ≥8 years weighing >45 kg: Azithromycin 1 g orally single dose OR doxycycline 100 mg orally twice daily for 7 days 1, 2
• Children <45 kg: Erythromycin base or ethylsuccinate 50 mg/kg/day orally divided into four doses daily for 14 days 1, 2
• Neonates with chlamydial conjunctivitis or pneumonia: Erythromycin base or ethylsuccinate 50 mg/kg/day orally divided into four doses daily for 14 days (approximately 80% effective) 1

Abstinence Period

Patients must abstain from all sexual intercourse for 7 days after initiating treatment (for single-dose therapy) or until completion of a 7-day regimen 3, 4, 2

• Abstinence must continue until all sex partners have completed treatment 3, 4, 2
• This 7-day period allows antibiotics to effectively clear the infection 4

Partner Management

All sex partners from the preceding 60 days must be evaluated, tested, and empirically treated. 3, 4, 2

• Treat the most recent partner even if last sexual contact was >60 days before diagnosis 3, 4
• Expedited Partner Therapy (EPT) is an effective alternative when partners are unlikely to seek medical care—clinicians can provide medications or prescriptions for patients to give to their partners 5, 6
• Partners should receive the same treatment regimen as the index patient 4

Retesting and Follow-Up

Routine test-of-cure is NOT recommended for non-pregnant patients treated with recommended regimens unless symptoms persist or reinfection is suspected. 3, 2

• Testing before 3 weeks post-treatment can yield false-positive results from dead organisms 3
• All women should be retested approximately 3 months after treatment due to reinfection rates reaching up to 39% in some populations 3, 1, 2
• Reinfection confers elevated risk for pelvic inflammatory disease compared to initial infection 3, 2
• Providers should rescreen all women whenever they next present for care within 12 months, regardless of whether partners were treated 3

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Gonorrhea

First-Line Treatment

Treat gonorrhea with ceftriaxone 250 mg IM as a single dose PLUS azithromycin 1 g orally as a single dose. 1, 7

• The dual therapy addresses both gonorrhea and presumptive chlamydia treatment, as coinfection rates are 20-40% in high-prevalence populations 1
• If gonorrhea is confirmed or prevalence is high (>5%), always treat for both infections concurrently 1

Abstinence Period

Patients must abstain from sexual activity for 7 days after receiving treatment, provided symptoms have resolved. 4

• Continue abstinence until all sex partners have been treated 4

Partner Management

• All sex partners from the previous 60 days should be evaluated, tested, and treated 4
• Expedited Partner Therapy is effective for gonorrhea when partners are unlikely to seek care 5, 6

Retesting

All patients treated for gonorrhea should be retested approximately 3 months after treatment due to high reinfection rates 4

• Test-of-cure is NOT routinely recommended for non-pregnant patients treated with recommended regimens 4

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Trichomoniasis

First-Line Treatment

Treat trichomoniasis with metronidazole 2 g orally as a single dose. 7

• Alternative: Metronidazole 500 mg orally twice daily for 7 days 7

Abstinence Period

Patients should abstain from sexual intercourse for 7 days after single-dose therapy or until completion of a 7-day regimen. 4

• Continue abstinence until all sex partners are treated 4

Partner Management

• All sex partners from the previous 60 days must be evaluated and treated 4
• Expedited Partner Therapy is appropriate for trichomoniasis 6

Retesting

Retest approximately 3 months after treatment due to high reinfection rates 4

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Syphilis

Treatment

Treat early syphilis (primary, secondary, or early latent) with penicillin G benzathine 2.4 million units IM as a single dose. 7

• Penicillin remains the most effective treatment for syphilis 7
• Serology using sequential testing to detect treponemal and nontreponemal antibodies is the recommended diagnostic method 7

Partner Management

• Contact tracing and treatment of sexual partners is essential for syphilis control 7

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Pelvic Inflammatory Disease (PID)

Treatment Approach

PID should ideally be treated in the hospital with parenteral antibiotics, using combinations of doxycycline, cefoxitin, clindamycin, aminoglycosides, or metronidazole. 8

• PID results from ascending infection with sexually transmitted pathogens (including gonorrhea and chlamydia) or components of normal vaginal flora 8
• 10-15% of PID cases result in infertility due to bilateral tubal occlusion 8

Partner Management

Sexual partners of patients with PID (both gonococcal and non-gonococcal) should be routinely examined and treated. 8

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Critical Pitfalls to Avoid

• Never use doxycycline, fluoroquinolones, or erythromycin estolate in pregnancy due to teratogenic risk or hepatotoxicity 3, 2
• Do not perform test-of-cure before 3 weeks post-treatment as nucleic acid tests can detect dead organisms, yielding false-positives 3
• Do not assume partners were treated—directly verify or use expedited partner therapy 1, 5, 6
• Do not wait for test results before treating partners—empiric treatment prevents ongoing transmission and complications 1
• Do not omit the 3-month retest for women with chlamydia or gonorrhea, as reinfection rates are extremely high and increase PID risk 3, 4, 2