Longitudinal Analysis of Obesity Drug Use and Public Awareness.

Importance: Obesity, a chronic disease with escalating global prevalence, poses considerable health risks. Glucagon-like peptide 1 receptor agonists (GLP-1RAs), including liraglutide, semaglutide, and tirzepatide, have demonstrated efficacy for weight loss in clinical trials. The paradigm shift in the approach to obesity management drugs (OMDs) may offer an opportunity to examine online search activity and prescription trends.

Objective: To investigate prescription patterns and online search trends for OMD and correlating usage dynamics with public engagement regarding these medications.

Design, Setting, And Participants: This repeated cross-sectional study analyzed online searches and corresponding data for dispensed prescriptions derived from the IQVIA National Prescription Audit, a comprehensive audit capturing approximately 90% of US retail prescription dispensing that is then projected to population-level data. Data from online searches and on prescriptions from the National Prescription Audit for US Food and Drug Administration-approved OMDs were collected from July 1, 2017, through February 29, 2024. This population-level analysis included all eligible individuals using either the Google search engine or receiving prescriptions.

Exposures: US monthly query fractions as online searches per 10 million total searches and monthly prescriptions dispensed for OMDs.

Main Outcome And Measures: Trends in OMD prescriptions and online searches were visually analyzed, and quantitative correlations were calculated using Spearman rank correlation.

Results: During the study period, 69 213 936 prescriptions for OMDs were dispensed in the US, with an overall increase of 0.76 to 0.80 million from July 2017 to June 2018 and 1.29 to 1.51 million from March 2023 to February 2024 and a mean (SD) annual growth rate of 5.3% (9.4%). Total monthly OMD prescriptions reached 1.5 million in February 2024, accounting for 0.41% of all prescriptions that month. Phentermine, semaglutide (Wegovy; Novo Nordisk), liraglutide (Saxenda; Novo Nordisk), and tirzepatide (Zepbound; Eli Lilly) were most prescribed. By February 2024, phentermine had approximately 0.74 million monthly prescriptions, Wegovy had 0.42 million, and Zepbound had 0.25 million. Most prescriptions were issued by advanced practice practitioners (APP) and primary care physicians (PCPs) and internists. The APPs' share increased from 25.3% in July 2017 to 40.6% in February 2024, while PCPs' and internists' share decreased from 57.9% to 48.1%. Wegovy's share of total OMDs increased to 27.7% and 28.3% and Zepbound's share to 16.1% and 16.5% (both February 2024) among APPs and PCPs and internists, respectively. Phentermine's dropped from 86.3% and 85.1% (July 2017) to 50.8% and 49.7% (February 2024), respectively. Online searches per 10 million reflected prescription trends, with Wegovy at 636.3, Zepbound at 468.9, and phentermine at 301.8 (all February 2024). The strongest correlations between prescriptions and search volumes were observed for semaglutide (Wegovy; r = 0.97) and tirzepatide (Zepbound; r = 0.90).

Conclusions And Relevance: This repeated cross-sectional study shows the dynamic growth and evolving share of new obesity medications since 2017 and a significant shift toward semaglutide and tirzepatide prescribing. The joint surge in prescriptions and online searches and their close correlation highlight the real-time associations between public awareness and prescription trends.