Over-the-counter weight loss drugs like Ozempic are delivering big results, but they face big questions. Three major reviews commissioned by the World Health Organization found that GLP-1 drugs, including tirsepatide (Mounjaro and Zepbound), semaglutide (Ozempic and Wegovy), and liraglutide (Victoza and Saxenda), lead to significant weight loss in people with obesity. Most of the studies were funded by drug manufacturers. Long-term safety data are still limited. Side effects such as nausea are common. Researchers draw attention to these facts.