Effects of GLP-1 Receptor Agonists on Psoriasis: An "Agent-Specific" Systematic Review of the Literature

Background: Psoriasis is a chronic inflammatory disease frequently associated with obesity and type 2 diabetes mellitus (T2DM). Glucagon-like peptide-1 receptor agonists (GLP-1RAs), widely used for T2DM and obesity, have demonstrated anti-inflammatory and immunomodulatory properties that may be relevant in psoriasis. However, individual GLP-1RAs differ substantially in their pharmacological characteristics and clinical effects. Our objective was to systematically review the available evidence on the effects of individual GLP-1RAs in patients with psoriasis. Methods: A systematic review was conducted according to PRISMA 2020 guidelines. PubMed and Scopus were searched up to April 2026 for studies evaluating GLP-1RAs in psoriasis. Case reports, case series, observational studies, and randomized controlled trials were included. Preclinical, clinical and safety outcomes were extracted and narratively synthesized. Results: Twenty-six studies met the inclusion criteria. Most involved patients with concomitant obesity and/or T2DM. Overall, semaglutide, liraglutide, exenatide, and tirzepatide were associated with improvements in psoriasis severity, often accompanied by reductions in body weight, glycated haemoglobin, inflammatory markers, and cardiometabolic risk factors. Semaglutide and liraglutide showed the most consistent evidence of benefit. Experimental and clinical data also suggested direct immunomodulatory effects on pathways involved in psoriasis pathogenesis. However, paradoxical psoriasiform eruptions and psoriasis exacerbations were reported with some agents. The evidence base was limited by the predominance of case reports and small observational studies, substantial heterogeneity, and the limited availability of randomized controlled trials. Conclusions: Current evidence suggests that GLP-1RAs may improve both psoriatic disease activity and cardiometabolic outcomes, particularly in patients with obesity or T2DM. Nevertheless, potential differences among individual agents warrant further investigation in larger controlled studies.