What are the treatments for common sexually transmitted diseases (STDs)?

Treatment of Common Sexually Transmitted Diseases

For common STDs, treatment should be based on the specific pathogen identified, with empiric therapy initiated before culture results when clinically indicated. The most frequently encountered STDs require targeted antimicrobial regimens that address gonorrhea, chlamydia, trichomoniasis, herpes, and syphilis 1.

Chlamydia trachomatis Infections

Single-dose azithromycin 1g orally is as effective as doxycycline 100mg twice daily for 7 days and should be preferred when compliance is a concern 1, 2.

• Recommended regimens:

  • Azithromycin 1g orally as a single dose 1, 2
  • OR Doxycycline 100mg orally twice daily for 7 days 1

• Clinical trials demonstrate 95-100% bacteriological cure rates with single-dose azithromycin versus 88-100% with doxycycline 3, 4

• Single-dose therapy eliminates compliance issues and can be directly observed in clinic settings 3

• Azithromycin is FDA-approved for urethritis and cervicitis due to C. trachomatis 2

Neisseria gonorrhoeae Infections

Ceftriaxone 125-250mg IM as a single dose is the cornerstone of gonorrhea treatment 1.

• Recommended regimen: Ceftriaxone 250mg IM in a single dose 1
• Must be combined with treatment for presumptive chlamydial coinfection (add doxycycline 100mg twice daily for 7-10 days) 1
• Azithromycin demonstrates 92-96% cure rates for gonorrhea but should not be used as monotherapy 5, 6

Trichomoniasis and Bacterial Vaginosis

Metronidazole 2g orally as a single dose effectively treats trichomoniasis and bacterial vaginosis 1.

• Single-dose metronidazole 2g orally is the standard regimen 1
• This regimen is included in prophylactic treatment for sexual assault victims 1

Genital Herpes (HSV)

For initial episodes, valacyclovir or famciclovir should be initiated within 72 hours of symptom onset; for recurrent episodes, treatment within 24 hours is critical 7, 8.

Initial Episode

• Valacyclovir is FDA-approved for treatment of initial genital herpes episodes in immunocompetent adults 7
• Treatment initiated >72 hours after symptom onset has unestablished efficacy 7

Recurrent Episodes

• Valacyclovir for treatment of recurrent episodes (efficacy established only when initiated within 24 hours) 7
• Famciclovir is approved for treatment of recurrent episodes 8

Suppressive Therapy

• Valacyclovir for chronic suppression in immunocompetent adults and HIV-infected patients 7
• Reduces transmission in discordant couples when combined with safer sex practices 7

Herpes Labialis (Cold Sores)

Valacyclovir or famciclovir should be initiated before vesicle formation for maximum efficacy 7, 8.

• Valacyclovir is approved for cold sores in patients ≥12 years 7
• Famciclovir is approved for recurrent herpes labialis 8
• Efficacy after development of clinical lesions (papule, vesicle, ulcer) is not established 7, 8

Epididymitis

Treatment must be stratified by patient age and likely pathogen: ceftriaxone plus doxycycline for age <35 years (sexually transmitted), fluoroquinolones for age >35 years (enteric organisms) 1.

Age <35 Years (Likely Chlamydia/Gonorrhea)

• Ceftriaxone 250mg IM single dose PLUS Doxycycline 100mg orally twice daily for 10 days 1

Age >35 Years (Likely Enteric Organisms)

• Ofloxacin 300mg orally twice daily for 10 days 1
• OR Levofloxacin 500mg orally once daily for 10 days 1

Adjunctive Measures

• Bed rest, scrotal elevation, and analgesics until fever and inflammation subside 1
• Failure to improve within 3 days requires diagnostic reevaluation 1

Mucopurulent Cervicitis (MPC)

Empiric treatment for both gonorrhea and chlamydia should be provided in high-prevalence populations or when follow-up is uncertain 1.

• Test for both C. trachomatis and N. gonorrhoeae with most sensitive tests available 1
• In high-prevalence settings: treat empirically for both pathogens 1
• In low-prevalence settings with reliable follow-up: await test results 1
• Most women with chlamydia or gonorrhea do NOT have MPC, so absence of cervicitis does not exclude infection 1

Proctitis (Sexually Acquired)

For acute proctitis in patients with receptive anal intercourse, treat empirically with ceftriaxone plus doxycycline pending specific diagnosis 1.

• Ceftriaxone 125mg IM (or another agent effective against anal/genital gonorrhea) PLUS Doxycycline 100mg orally twice daily for 7 days 1
• Evaluate for HSV, N. gonorrhoeae, C. trachomatis, and T. pallidum 1
• Treat based on anoscopy findings or polymorphonuclear leukocytes on Gram stain 1

Sexual Assault Prophylaxis

Prophylactic triple therapy covering gonorrhea, chlamydia, and trichomoniasis should be offered to sexual assault victims due to difficulty with follow-up 1.

• Ceftriaxone 125mg IM single dose PLUS Metronidazole 2g orally single dose PLUS Doxycycline 100mg orally twice daily for 7 days 1
• Hepatitis B vaccination should be initiated 1
• HIV prophylaxis is not routinely recommended but HIV counseling and testing should be offered 1

Partner Management

All sex partners within 60 days of symptom onset (or diagnosis if asymptomatic) must be evaluated and treated for the same infection as the index patient 1.

• Partners should receive treatment even if asymptomatic 1
• Sexual abstinence until both patient and partners complete therapy and are symptom-free 1
• For symptomatic patients, partners with contact within 30 days of symptom onset require treatment 1

Special Populations

HIV-Infected Patients

• Treatment regimens for gonorrhea, chlamydia, MPC, and epididymitis are identical to HIV-negative patients 1
• Fungi and mycobacteria are more likely causes of epididymitis in immunosuppressed patients 1
• Valacyclovir is approved for suppression of genital herpes in HIV-infected adults with CD4+ ≥100 cells/mm³ 7

Pregnant Women

• Lindane is contraindicated in pregnant/lactating women 1
• Treatment of chlamydia in pregnancy prevents neonatal transmission 1

Critical Follow-Up Considerations

• Chlamydia/Gonorrhea: Patients with persistent symptoms after treatment require reevaluation for reinfection versus treatment failure 1
• Epididymitis: Failure to improve within 3 days mandates reassessment; persistent swelling after antimicrobial completion requires comprehensive evaluation for tumor, abscess, testicular cancer, or fungal/tuberculous infection 1
• Sexual assault victims: Repeat STD testing at 2 weeks and serologic testing for syphilis/HIV at 12 weeks 1