Management of Hives Following Doxycycline in Non-Gonococcal Urethritis
Discontinue doxycycline immediately and switch to azithromycin 1 g orally as a single dose, as this represents a likely allergic reaction requiring alternative therapy. 1, 2
Immediate Action Required
- Stop doxycycline immediately upon development of hives, as this represents a hypersensitivity reaction that could progress to more severe manifestations 2
- Small hives indicate an IgE-mediated allergic response that contraindicates continued tetracycline use 1
Alternative Treatment Regimen
Switch to azithromycin 1 g orally as a single dose, which is the CDC-recommended alternative for non-gonococcal urethritis and avoids cross-reactivity with tetracyclines 1, 3, 4
Additional Alternative Options (if azithromycin contraindicated):
- Erythromycin base 500 mg orally four times daily for 7 days 1, 3
- Erythromycin ethylsuccinate 800 mg orally four times daily for 7 days 1, 3
- Levofloxacin 500 mg orally once daily for 7 days 3, 5
- Ofloxacin 300 mg orally twice daily for 7 days 1, 5
Symptomatic Management
- Administer antihistamines for symptomatic relief of hives (e.g., diphenhydramine or hydroxyzine) 1
- Monitor for progression to angioedema, respiratory symptoms, or anaphylaxis, which would require emergency intervention 1
Partner Management Remains Critical
- All sexual partners with contact within 60 days of diagnosis must be evaluated and treated with an appropriate alternative regimen (not doxycycline) 1, 3, 4
- Both patient and partners should abstain from sexual intercourse for 7 days after single-dose azithromycin therapy 4, 5
Follow-Up Strategy
- Patients should return for evaluation if symptoms persist or recur after completing alternative therapy 1
- Test-of-cure is not routinely recommended after azithromycin unless symptoms persist or reinfection is suspected 4, 5
- Document the doxycycline allergy prominently in the medical record to prevent future exposure 2
Critical Clinical Considerations
- The clinical cure rate for azithromycin single-dose therapy (81%) is comparable to doxycycline (77%) for NGU, making it an excellent alternative 6
- Azithromycin has the added advantage of single-dose administration, eliminating compliance concerns that may arise with multi-day regimens 7, 6
- While both azithromycin and doxycycline show declining efficacy against Mycoplasma genitalium (40% vs 30% cure rates), azithromycin remains appropriate first-line alternative therapy 8
Common Pitfall to Avoid
- Do not attempt desensitization for doxycycline-induced hives - desensitization protocols described in guidelines are specific to penicillin allergy for critical infections like syphilis, not for tetracyclines where excellent alternatives exist 1
- Do not use other tetracyclines (minocycline, tetracycline) as alternatives, as cross-reactivity within the tetracycline class is common 2