Impact of Semaglutide Introduction on the Use of Concomitant Medications: An Interrupted Time Series

Aims To evaluate the impact of semaglutide initiation for weight management on the use of concomitant medications commonly prescribed for obesity‐related comorbidities. Materials and Methods We conducted a nationwide interrupted time series study using data from Danish registers, including adults initiating semaglutide for weight management between 12/2022 and 12/2024. Monthly prescriptions for 10 medication classes were analysed in the 24 months before and 12 months after initiation. Effects at 12 months were expressed as rate ratios (RRs) comparing observed values with expected values based on pre‐initiation trends. Results Among 189 392 semaglutide initiators (68% women; median age 50 years), prescription volumes at 12 months declined and were lower than projected from pre‐initiation trends for antiasthmatics (RR: 0.82, 95% confidence interval 0.79–0.86), topical corticosteroids (0.91, 0.87–0.96), antipsoriatics (0.91, 0.83–1.00), analgesics (0.93, 0.90–0.96), antidepressants (0.93, 0.89–0.98) and topical antifungal formulations (0.92, 0.86–0.99). Antihypertensive prescriptions continued to rise after semaglutide initiation, but more slowly than projected (0.92, 0.89–0.95). Glucose‐lowering medications declined (0.87, 0.82–0.92), mainly non‐insulin agents, but a similar reduction was observed in the negative control cohort. Anxiolytic use increased (1.16, 1.08–1.24) and remained elevated at 2 years. Changes in lipid‐modifying agents and medications for gastric acid disorders were small or transient. Conclusions Semaglutide initiation for weight management was associated with reduced use of several concomitant medications for obesity‐related comorbidities, while anxiolytic use increased. Changes in other therapeutic classes were limited. These findings suggest that semaglutide treatment may influence overall medication use and support continued monitoring of prescribing patterns during therapy.