Not All GLP-1 Receptor Agonists Are Alike: Real-World Evidence of Differential Endocrine and Dermatologic Safety.

AIMS: Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) are widely used for metabolic disorders, but emerging safety concerns include alopecia and reproductive or endocrine-related adverse events (AEs). This study investigated the association between specific GLP-1 RAs and these endocrine-related AEs using a large-scale pharmacovigilance database. MATERIALS AND METHODS: This study analysed the U.S. FDA Adverse Event Reporting System (FAERS) data (Q2 2022-Q2 2025) for six GLP-1 Ras (exenatide, lixisenatide, liraglutide, dulaglutide, semaglutide, and tirzepatide) to identify alopecia- and reproductive or endocrine-related a AEs. Disproportionality analyses were conducted using crude and adjusted reporting odds ratios (cROR and aROR) from logistic regression controlling for potential confounding factors. Sensitivity analyses with positive and negative controls were used to validate the signal robustness. RESULTS: A total of 1276 alopecia-related and 759 reproductive or endocrine-related cases were identified. Semaglutide showed significant positive associations with alopecia (aROR 1.23 [1.11-1.35]) and reproductive/hormonal disorders, including polycystic ovary syndrome (aROR 6.59 [3.73-11.64]) and menstrual abnormalities. In contrast, dulaglutide and tirzepatide demonstrated negative associations for several reproductive outcomes (e.g., dysmenorrhoea, amenorrhoea, heavy menstrual bleeding), indicating lower reporting odds in this dataset. Sensitivity analyses using control drugs confirmed the consistency and specificity of these findings. CONCLUSION: This real-world pharmacovigilance study identified agent-specific differences in the endocrine and dermatologic safety profiles of GLP-1 RAs. While semaglutide exhibited disproportionate reporting for alopecia and hormonal imbalance, dulaglutide and tirzepatide showed lower or non-significant disproportionality signals for these events. These results highlight the need for personalised agent selection and continued pharmacovigilance to optimise long-term patient safety.