Antibiotic of Choice for Epididymitis in Sexually Active Males Under 35
For a sexually active male under 35 with epididymitis, the antibiotic of choice is ceftriaxone 250 mg IM as a single dose PLUS doxycycline 100 mg orally twice daily for 10 days. 1, 2
Rationale for This Regimen
This dual-therapy approach targets the two most common pathogens in this age group:
- Chlamydia trachomatis and Neisseria gonorrhoeae are the predominant causative organisms in sexually active men aged 14-35 years 1, 3, 4
- Ceftriaxone provides immediate coverage against N. gonorrhoeae, including resistant strains 1
- Doxycycline covers C. trachomatis, which accounts for two-thirds of cases previously labeled as "idiopathic epididymitis" in young men 4, 5
- The 10-day duration of doxycycline is critical for adequate treatment of chlamydial infection 1, 6
Alternative Regimen
If the dual-therapy regimen is not feasible, fluoroquinolone monotherapy can be used:
- Ofloxacin 300 mg orally twice daily for 10 days 1
- OR levofloxacin 500 mg orally once daily for 10 days 2, 7
Important caveat: Fluoroquinolones were historically contraindicated in persons ≤17 years of age 1, though this has evolved with newer formulations. However, the dual-therapy regimen remains preferred for sexually transmitted epididymitis in young adults.
Special Population: Men Who Practice Insertive Anal Intercourse
For men who have insertive anal intercourse, modify the regimen to cover enteric organisms:
- Ceftriaxone 250 mg IM single dose PLUS levofloxacin 500 mg orally once daily for 10 days 3
- OR ceftriaxone 250 mg IM single dose PLUS ofloxacin 300 mg orally twice daily for 10 days 3
This modification is necessary because Escherichia coli and other enteric bacteria can cause sexually transmitted epididymitis in this population 1
Diagnostic Confirmation Before Treatment
Empiric therapy should be initiated immediately, but obtain these diagnostic tests: 1
- Gram-stained smear of urethral exudate or intraurethral swab (≥5 polymorphonuclear leukocytes per oil immersion field indicates urethritis) 1, 2
- Culture or nucleic acid amplification test for N. gonorrhoeae 1, 2
- Test for C. trachomatis from intraurethral swab 1, 2
- Gram-stained smear and culture of uncentrifuged urine for Gram-negative bacteria 1
Critical pitfall: Current tests for C. trachomatis lack sufficient sensitivity to exclude infection, so empiric coverage is mandatory even with negative initial testing 1
Adjunctive Measures
In addition to antibiotics, recommend: 1, 2
- Bed rest until fever and local inflammation subside 1, 2
- Scrotal elevation 1, 2
- Analgesics for pain control 2
Follow-Up and Red Flags
Reassess within 3 days of initiating therapy: 1, 2
- Failure to improve requires re-evaluation of both diagnosis and treatment 1
- Consider hospitalization if no improvement 1
- Persistent swelling and tenderness after completing antimicrobial therapy warrants evaluation for testicular cancer, tuberculous epididymitis, or fungal epididymitis 1, 2
Emergency consideration: Testicular torsion must be ruled out, especially when pain onset is sudden and severe, as this is a surgical emergency requiring intervention within 4-6 hours 2, 8
Partner Management
Sex partners require evaluation and treatment: 1, 2
- Refer partners who had contact within 60 days preceding symptom onset 2
- Treat partners empirically with regimens effective against both C. trachomatis and N. gonorrhoeae, regardless of the patient's culture results 1
- Female partners of men with C. trachomatis epididymitis have high rates of infection and may develop pelvic inflammatory disease if untreated 4, 5
- Instruct patients to avoid sexual intercourse until both patient and partner(s) complete therapy and are symptom-free 1, 2
HIV-Infected Patients
Patients with HIV should receive the same initial regimen (ceftriaxone plus doxycycline): 2, 7