The U.S. Food and Drug Administration (FDA) has approved Eli Lilly and Company’s tirzepatide injections for chronic weight management in adult patients who are obese, overweight or present with at least one weight-related condition such as high blood pressure or high cholesterol. These weekly injections are being sold and distributed under the brand name Zepbound.

Tirzepatide is also the active ingredient in another Eli Lilly and Company offering, Mounjaro, which gained FDA approval in May 2022 for improving glycemic control among adults with type 2 diabetes. Mounjaro is also taken once per week.

“Obesity and overweight are serious conditions that can be associated with some of the leading causes of death such as heart disease, stroke and diabetes,” John Sharretts, MD, director of the division of diabetes, lipid disorders, and obesity in the FDA’s Center for Drug Evaluation and Research, said in a statement from the agency. “In light of increasing rates of both obesity and overweight in the United States, today’s approval addresses an unmet medical need.”

According to the FDA, the dosage of tirzepatide patients take must be increased over four to 20 weeks to achieve maximum results. The agency also emphasized that the drug is most effective when taken in combination with a reduced-calorie diet and physical activity.

The same FDA statement also highlighted another key point: Patients should not be taking the two approved forms of tirzepatide, Zepbound and Mounjaro, at the same time. In addition, it is not clear how the body may react to taking tirzepatide and another medication for weight management at the same time.