Incidence of acne in patients with inflammatory bowel disease treated with Janus kinase inhibitors: a systematic review and meta-analysis

Inflamm Bowel Dis. 2026 Mar 5:izag032. doi: 10.1093/ibd/izag032. Online ahead of print.

Abstract

Background: Janus kinase (JAK) inhibitors are effective oral therapies for inflammatory bowel disease (IBD). While acne is a known adverse event in dermatological cohorts, its incidence and risk factors in the IBD population are not well-defined. We aimed to determine the pooled incidence of acne in IBD patients treated with JAK inhibitors and to explore this risk across key clinical subgroups.

Methods: We conducted a systematic review and meta-analysis following PRISMA guidelines. MEDLINE, EMBASE, and CENTRAL were searched from inception to September 2025 for randomized controlled trials (RCTs) and observational studies reporting acne incidence in IBD patients on JAK inhibitors. Data were pooled using a random-effects generalized linear mixed-effects model. Pre-specified subgroup analyses were performed.

Results: A total of 50 studies (5 RCTs, 45 observational) involving 9902 IBD patients were included. The overall pooled incidence of acne was 8.6% (95% CI: 6.4%-11.6%). Acne rates were significantly higher (P < .0001) with the upadacitinib (12.2%), compared to tofacitinib (2.6%) and filgotinib (2.3%). A numerically higher incidence was observed during induction (8.6%) versus maintenance (4.2%) therapy, though this difference was not statistically significant (P = .07). The incidence was significantly higher in the pediatric population (12.2%) compared to adults (7.4%) (P = .03). In RCTs, JAK inhibitors were associated with significantly increased odds of acne compared to placebo (OR 2.43, 95% CI: 1.33-4.43, P = .019). No statistically significant difference was observed by IBD subtype.

Conclusion: Acne is a common adverse event in IBD patients treated with JAK inhibitors. The reported incidence of acne was significantly higher with upadacitinib, in the pediatric population, and numerically higher during the induction phase of treatment.

Keywords: Crohn’s disease; IBD; JAK inhibitor; acne; ulcerative colitis.

Plain language summary

This systematic review and meta-analysis of 9902 IBD patients found an 8.6% incidence of acne with JAK inhibitors. The risk is significantly higher with upadacitinib and in pediatric patients, providing key data for clinical counseling.