What is the immediate treatment recommendation for a patient diagnosed with a sexually transmitted infection (STI)?

Immediate Treatment Recommendations for Sexually Transmitted Infections (STIs)

Immediate treatment for a diagnosed STI should begin with pathogen-specific antimicrobial therapy based on the identified organism, with doxycycline 100 mg orally twice daily for 7 days as first-line treatment for chlamydial infections and ceftriaxone for gonococcal infections. 1

Treatment by Specific STI

Chlamydia

• First-line treatment: Doxycycline 100 mg orally twice daily for 7 days (95.5% efficacy for urogenital infections, 96.9% for rectal infections) 1, 2
• Alternative treatment: Azithromycin 1 g orally in a single dose (92% efficacy for urogenital infections) - recommended when adherence is a concern 1, 3
• During pregnancy: Erythromycin 500 mg orally four times daily for 7 days or amoxicillin 500 mg orally three times daily for 7 days 1, 4

Gonorrhea

• Recommended regimen: Ceftriaxone 125 mg IM in a single dose 5
• For disseminated gonococcal infection: Ceftriaxone 1 g IM or IV every 24 hours 5
• Co-treatment: Always treat for possible chlamydial co-infection with doxycycline or azithromycin 1

Syphilis

• Primary syphilis: Benzathine penicillin G as first-line therapy 6
• For penicillin-allergic patients: Doxycycline 100 mg orally twice daily for 2 weeks 2

Trichomoniasis

• Recommended regimen: Metronidazole 2 g orally in a single dose 5

Partner Management

1. All sexual partners from the preceding 60 days should be evaluated, tested, and treated 1
2. Most recent partner should be treated even if the last sexual contact was more than 60 days before diagnosis 1
3. Patients and partners should abstain from sexual intercourse until:
   • 7 days after single-dose therapy completion
   • Until completion of a 7-day regimen 1

Follow-up Recommendations

• Retesting: Approximately 3 months after treatment due to high risk of reinfection (up to 39% in some studies) 1
• Test of cure: Generally not needed after completing treatment with doxycycline or azithromycin unless symptoms persist 1
• For erythromycin treatment: Consider test of cure 3 weeks after completion 1

Special Considerations

Pregnancy

• Doxycycline is contraindicated during pregnancy 1
• Use erythromycin or amoxicillin for chlamydial infections 1, 4
• For gonorrhea, use recommended cephalosporin regimens; avoid quinolones 5

HIV Co-infection

• Same treatment regimens are recommended for HIV-negative and HIV-positive patients 1
• More vigilant follow-up may be necessary 7

Sexual Assault Cases

• Empiric antimicrobial regimen recommended:
  • Ceftriaxone 125 mg IM in a single dose, PLUS
  • Metronidazole 2 g orally in a single dose, PLUS
  • Azithromycin 1 g orally in a single dose OR Doxycycline 100 mg orally twice daily for 7 days 5

Common Pitfalls to Avoid

1. Failing to treat partners: Partner treatment is crucial to prevent reinfection 1
2. Inadequate follow-up: High reinfection rates necessitate retesting approximately 3 months after treatment 1
3. Missing co-infections: Patients with chlamydia often have concurrent gonorrhea requiring dual therapy 1
4. Poor adherence: When possible, medications should be dispensed on site and first dose directly observed 1
5. Incomplete treatment: Ensure full course completion, especially for multi-day regimens 7

Maximizing Treatment Success

• Provide medications on-site when possible 1
• Directly observe first dose administration 1
• Consider single-dose therapy when adherence is a concern 1, 8
• Educate patients about consistent condom use to reduce reinfection risk 1
• Ensure patients understand the importance of partner treatment 1

By following these evidence-based recommendations, healthcare providers can effectively treat STIs, reduce complications, and prevent transmission to others.