Comparative Efficacy of Oral Isotretinoin and Acitretin in Adults with Hidradenitis Suppurativa: A Systematic Review and Meta-analysis

Background: Hidradenitis Suppurativa (HS) is a chronic inflammatory skin condition with painful nodules, abscesses, significant scarring and decreased quality of life. Systemic retinoids, isotretinoin and acitretin are often used off-label for HS, though their efficacy and safety remain unclear. Materials and Methods: Studies on isotretinoin and acitretin for HS treatment were reviewed and identified. Inclusion criteria focused on studies reporting efficacy (complete or partial improvement) and adverse effects. A meta-analysis was performed to estimate pooled prevalence rates of treatment responses and side effects. This meta-analysis used data from 9 studies on isotretinoin and 7 on acitretin. Results: Isotretinoin was associated with a 29.8% (95% confidence interval [CI]: 16.4%–43.2%) prevalence of complete or partial improvement in HS patients, whereas 56.9% (95% CI: 38.0%–75.8%) showed no response. Isotretinoin side effects were observed in 3.3% (95% CI: 0.2%–6.3%) of cases. Acitretin demonstrated a higher rate of efficacy, with 70.8% (95% CI: 49.9%–91.7%) of patients achieving complete or partial improvement, but side effects were more prevalent at 43.1% (95% CI: 0.8%–85.4%). Conclusions: Both isotretinoin and acitretin show potential as HS treatments. Acitretin demonstrates superior efficacy but a higher risk of adverse effects. Isotretinoin, while less effective, showed fewer side effects, making it a viable alternative for patients who may be intolerant to acitretin. Further randomised controlled trials are needed to define the role of systemic retinoids in HS treatment, optimise dosing strategies and assess long-term outcomes.