Topical Antibiotic Treatment for Hidradenitis Suppurativa
Topical clindamycin 1% solution or gel applied twice daily for 12 weeks is the only evidence-based topical antibiotic for hidradenitis suppurativa, but it should be combined with benzoyl peroxide to reduce the high risk of Staphylococcus aureus resistance. 1, 2
Evidence Base for Topical Clindamycin
Clindamycin 1% is the only topical antibiotic that has been studied in randomized controlled trials for hidradenitis suppurativa. 1 A 12-week placebo-controlled trial of 27 patients with Hurley stage I or II disease demonstrated that topical clindamycin reduced pustules but had no effect on inflammatory nodules and abscesses. 1 Patient self-assessment showed improvement, though the medication's efficacy is limited to superficial lesions. 1
In a comparative trial of 46 patients with mild-to-moderate disease, topical clindamycin performed similarly to oral tetracycline 500 mg twice daily, with no significant difference between the two treatments. 3 This suggests topical therapy can be as effective as systemic antibiotics for mild disease. 3
Critical Limitation: Antibiotic Resistance
The major pitfall of topical clindamycin monotherapy is that it significantly increases rates of Staphylococcus aureus resistance in patients with hidradenitis suppurativa. 1 To mitigate this risk, benzoyl peroxide should be added to the regimen. 1
A 2023 randomized controlled trial directly compared clindamycin-benzoyl peroxide gel with clindamycin lotion alone in 10 patients with mild to moderate disease. 2 Both treatments led to significant improvements in disease severity scores (IHS4 decreased by -2 for combination gel vs -1.5 for clindamycin alone at 16 weeks, both p<0.05), and pain scores improved substantially in both groups. 2 The combination therapy showed favorable clinical efficacy similar to clindamycin alone while theoretically preventing antibiotic resistance. 2
Adjunctive Topical Therapies
Beyond antibiotics, several topical agents have supporting evidence:
Antiseptic washes with chlorhexidine, benzoyl peroxide, or zinc pyrithione are recommended based on expert opinion, though no specific data exist comparing agents. 1
Resorcinol 15% cream (a keratolytic and antiseptic) was studied in 12 women with Hurley stage I or II disease and reduced pain and duration of abscesses when applied twice daily for flares and daily between flares. 1 However, irritant dermatitis occurs frequently, limiting tolerability. 1, 4
Intralesional triamcinolone 10 mg/mL (0.2-2.0 mL injected into inflamed lesions) demonstrated significant reductions in erythema, edema, suppuration, and lesion size in a prospective case series. 1, 4 Pain visual analog scale scores improved significantly after just 1 day. 1
When Topical Therapy Is Appropriate
Topical clindamycin is recommended as first-line therapy specifically for mild disease (Hurley stage I) with predominantly superficial pustules rather than deep nodules or abscesses. 1, 4 The North American guidelines explicitly state that topical clindamycin may reduce pustules but has no effect on inflammatory nodules and abscesses. 1
For patients with moderate disease (Hurley stage II) or those with abscesses and inflammatory nodules, systemic antibiotics are more appropriate. 1 The combination of oral clindamycin 300 mg twice daily with rifampicin 300-600 mg daily for 10-12 weeks is recommended as second-line therapy for moderate disease or first-line for severe disease. 1, 5
Treatment Duration and Monitoring
The standard treatment duration for topical clindamycin is 12 weeks. 1, 4 After completing the course, consider a treatment break to assess the need for ongoing therapy and limit antimicrobial resistance development. 4, 5 Response should be assessed using reduction in pustule count, patient-reported pain scores, and quality of life measures. 1
Common Pitfalls to Avoid
- Do not use topical clindamycin monotherapy without benzoyl peroxide due to resistance concerns. 1, 2
- Do not expect topical clindamycin to treat deep nodules, abscesses, or sinus tracts—it only works for superficial pustular lesions. 1
- Do not continue topical antibiotics indefinitely without treatment breaks, as this promotes resistance without clear benefit. 4, 5
- Do not use topical clindamycin as monotherapy for moderate-to-severe disease—these patients require systemic antibiotics or biologics. 1