Patients prescribed GLP-1 medications may face a "significantly increased" risk of bone fractures and tendon tears, according to a new observational study whose lead author said he launched the research after seeing patients develop serious tendon injuries from minor accidents.
The study examined medical records to compare outcomes between patients taking the drugs — a class that includes Ozempic, Wegovy, and Mounjaro — and those who were not. The lead author said his interest began after some of his own patients "developed serious tendon tears following relatively minor injuries," prompting him to investigate whether the medications affect bone and other connective tissue.
The findings have not yet been peer reviewed, a step that outside physician Dr. Laudenslager called "essential" to the scientific process. Until that review is complete, he said, there is "no sound scientific evidence" to support changing clinical practice based on the results.
Laudenslager, who was not involved in the research, also noted that the study is observational in nature — it identified a correlation between GLP-1 use and connective-tissue injuries, not a cause-and-effect relationship. That distinction matters because patients on GLP-1s often lose weight rapidly, and weight loss itself is a known factor in bone density changes.
The study carries at least three other limitations. It relied entirely on medical records, meaning it assumed every patient prescribed a GLP-1 actually took the medication as directed. It also did not account for exercise habits, nutritional intake, or other lifestyle factors that commonly influence bone health. And because the data came from existing records rather than a controlled trial, researchers could not randomly assign patients to treatment and comparison groups.
GLP-1 receptor agonists work by mimicking a gut hormone that regulates appetite and blood sugar, and they have become among the most prescribed drugs in the United States since their approval for weight management. Roughly 1 in 8 American adults report having used one, according to a 2024 KFF survey.
Bone health is a particular concern for the patient populations most likely to use these drugs. Postmenopausal women, who make up a large share of GLP-1 users, already face elevated osteoporosis risk, and rapid weight loss is associated with reduced bone mineral density in older adults. Tendon injuries, while less common, can require surgery and months of rehabilitation.
The researchers did not report the size of the study population or the specific fracture and tear rates observed. A peer-reviewed version would need to disclose those figures and adjust for the confounding variables the current analysis omits before clinicians could weigh the findings against the cardiovascular and metabolic benefits GLP-1s have demonstrated in randomized trials.
