What is the recommended dosage of doxycycline (antibiotic) for treating hidradenitis suppurativa?

Doxycycline Dosage for Hidradenitis Suppurativa

For hidradenitis suppurativa, doxycycline should be dosed at 100 mg once or twice daily for 12 weeks as first-line oral antibiotic therapy for mild-to-moderate disease (Hurley Stage I), but it is NOT recommended as first-line for Hurley Stage II disease with abscesses or inflammatory nodules. 1, 2

Specific Dosing Regimens

Standard Dosing

• Doxycycline 100 mg once daily OR twice daily for 12 weeks is the recommended initial regimen 1, 2
• Treatment can be extended up to 4 months (16 weeks) for more widespread mild disease 1, 2
• The British Association of Dermatologists specifically recommends lymecycline 408 mg or doxycycline 100 mg once or twice daily for 12 weeks 1

Alternative Dosing

• Doxycycline 200 mg once daily was used in the THESEUS prospective cohort study, though fidelity was only 52% after 3 months due to lack of effectiveness and adverse effects 3, 4
• Subantimicrobial modified-release doxycycline 40 mg once daily demonstrated comparable efficacy to regular-release doxycycline 100 mg twice daily, achieving HiSCR in 64% vs 60% of patients respectively 5

Critical Treatment Algorithm

When to Use Doxycycline

• Hurley Stage I disease (isolated nodules without sinus tracts or scarring) after topical clindamycin 1% has been tried 2
• Mild-to-moderate disease as first-line oral antibiotic 1, 2, 6
• As an alternative to lymecycline 408 mg or tetracycline 500 mg twice daily 1, 2

When NOT to Use Doxycycline

• Do NOT use as first-line for Hurley Stage II disease with deep inflammatory lesions or abscesses, as it has minimal effect on these lesions 2
• Doxycycline was not independently linked to better outcomes when combined with adalimumab in the PIONEER studies 1

Treatment Response Assessment

Reassessment at 12 Weeks

• Measure pain using Visual Analog Scale (VAS) 1, 2
• Count inflammatory lesions 1, 2
• Assess quality of life using Dermatology Life Quality Index (DLQI) 1, 2

Escalation Criteria

• If no clinical response after 12 weeks, escalate to clindamycin 300 mg twice daily PLUS rifampicin 300-600 mg daily for 10-12 weeks 1, 2
• The clindamycin-rifampicin combination demonstrates response rates of 71-93% in systematic reviews, far superior to doxycycline monotherapy 1, 2

Evidence Quality and Limitations

Weak Evidence Base

• Only one randomized controlled trial exists comparing tetracycline 500 mg twice daily to topical clindamycin, showing modest 30% abscess reduction with no significant improvement in patient-reported outcomes 1, 2
• Doxycycline has been evaluated primarily in combination with biologics where it showed no independent benefit 1, 2

Comparative Effectiveness

• In a prospective study of 108 patients, tetracycline provided the greatest clinical improvement measured by Hidradenitis Suppurativa Score compared to doxycycline and lymecycline 7
• Higher reduction in HSS was significantly associated with lower BMI, Hurley stage III, higher baseline HSS, and higher number of boils at baseline 7

Critical Pitfalls to Avoid

• Avoid long-term antibiotic use without treatment breaks to reduce antimicrobial resistance risk 1, 2
• Do not continue doxycycline beyond 4 months without reassessment, as prolonged use increases antimicrobial resistance risk without proven additional benefit 2
• Do not use for Hurley Stage III disease as first-line; these patients require immediate clindamycin-rifampicin combination or biologics 1, 2

Essential Adjunctive Measures

Regardless of antibiotic choice, always address:

• Smoking cessation referral 1, 2
• Weight management referral if BMI elevated 1, 2
• Pain management with NSAIDs for symptomatic relief 1, 2
• Appropriate wound dressings for draining lesions 1, 2
• Screen for depression/anxiety and cardiovascular risk factors (blood pressure, lipids, HbA1c) 1, 2