Researchers Pinpoint Unreported Weight Loss Injection Side-Effects Affecting Mounjaro and Wegovy Users

Analyzing over 400,000 posts on the online forum Reddit, researchers identified patient-reported symptoms that are not well captured in clinical trials, including irregular menstrual cycles and fever-like sensations such as chills and hot flushes. The findings highlight a potential gap between official trial data and real-world patient experiences.

Conducted by scientists at the University of Pennsylvania, the study found that around 44 percent of weight-loss injection users reported at least one side effect, most commonly digestive issues such as nausea and stomach pain, followed by fatigue. Notably, about 4 percent of users mentioned menstrual irregularities – such as missed periods or unusually heavy bleeding – though the researchers suggested this figure could be even higher. Reports of temperature-related symptoms, including feeling unusually cold or experiencing fever-like chills, were also flagged as areas needing further investigation.

With millions of people worldwide now using weight-loss injections – and around 1.6 million in the UK alone – the researchers say real-world data from online communities may provide important early warning signs regarding side effects.

To learn the truth about the weight-loss industry, see this article by Dr. Aleksandra Niedzwiecki on our website.