Efficacy and Safety of Isotretinoin Plus Desloratadine versus Isotretinoin Alone for Acne Vulgaris: Systematic Review and Meta-analysis

Introduction: Acne vulgaris is a common inflammatory skin disorder affecting the sebaceous glands–rich areas, including the face, chest, and back. It typically arises during adolescence but can persist or appear in adulthood. Recent findings suggest that histamine, via H1 receptors on sebocytes, further contributes to inflammation and sebum secretion. Desloratadine, an H1 receptor antagonist, has anti-inflammatory effects and reduces sebum squalene levels, supporting potential as an adjunctive acne therapy. We assessed whether adding desloratadine to isotretinoin improves outcomes compared to isotretinoin monotherapy. Methods: Following PRISMA guidelines, we searched PubMed, Web of Science, and Scopus targeting randomized controlled trials (RCTs) comparing isotretinoin plus desloratadine versus isotretinoin alone. Eligible studies reported the Global Acne Grading System (GAGS) score, inflammatory lesion count, or non-inflammatory lesion count. Results were pooled and expressed as differences (MD) with 95% confidence intervals (CI). Results: Six RCTs, including 424 patients, met the inclusion criteria. Combination therapy demonstrated greater improvement in GAGS score (pooled MD −1.81, 95% CI [−2.52; −1.1], P < 0.00001). However, no significant differences were observed in inflammatory lesions (pooled MD 0.26, 95% CI [−1.01; 1.54], P = 0.68) or non-inflammatory lesions (pooled MD 0.30, 95% CI [−2.24; 2.84], P = 0.82). The addition of desloratadine to isotretinoin improved treatment efficacy and showed trends toward fewer flares and dry lips, although these differences did not reach statistical significance. Conclusion: Desloratadine appears to enhance the efficacy and tolerability of isotretinoin, supporting its position as a promising adjunctive therapy for acne management.