Among 860 Brazilian adults currently or previously using GLP-1 receptor agonists (GLP-1 RAs) for weight loss, 23.8% (95% CI: 21.1–26.8%) reported using these medications without a medical prescription. Poisson regression identified working in healthcare-related professions (PR = 1.45), not having obesity (PR = 1.45), and avoiding structured gym environments (PR = 1.55) as independent predictors of self-medication, while having diabetes (PR = 0.35), being married (PR = 0.73), or having eating disorders (PR = 0.72) were protective against unsupervised use.
The finding that healthcare workers are among the most likely to self-prescribe GLP-1 RAs is counterintuitive but not unprecedented — clinical familiarity often lowers perceived risk thresholds, a pattern documented with antibiotics and benzodiazepines. More broadly, this mirrors a global phenomenon: as semaglutide and tirzepatide achieve near-cultural saturation through social media, informal procurement has surged. The risk is non-trivial. GLP-1 RAs carry real adverse effect profiles — pancreatitis, gallbladder disease, thyroid C-cell concerns — and require baseline screening and monitoring that self-medicators bypass entirely. The "not obese" subgroup is particularly concerning; these individuals lack the metabolic justification that informs clinical risk-benefit calculus. Limitations include the online convenience sample (82% female, self-reported), which skews toward digitally engaged users and likely underrepresents lower-income populations. This is confirmatory rather than paradigm-shifting, but it quantifies an urgent regulatory and public health gap as GLP-1 access continues to outpace prescribing infrastructure worldwide.