Health Risks Emerge from Compounded Weight-Loss Drugs

Eli Lilly has identified health risks from compounded weight-loss drugs combining vitamin B12 and tirzepatide, the key ingredient in Zepbound. Testing revealed impurities from a chemical reaction between tirzepatide and B12, posing unknown risks. Lilly has called for a recall and notified the FDA, highlighting potential legal and safety issues.

In a public letter released on Thursday, pharmaceutical giant Eli Lilly warned consumers about potential health risks from compounded weight-loss drugs that combine vitamin B12 with tirzepatide, the active ingredient in the company's Zepbound medication. According to Lilly, these compounded drugs contain an impurity caused by a chemical reaction between the ingredients, a finding based on their testing of samples from various sources.

The company has been actively pursuing legal actions against those marketing what it claims are unauthorized copies of Zepbound and Mounjaro, a diabetes treatment sharing the same ingredient. Some compounders assert their products are legal under specific federal provisions allowing tailored formulations when necessary for individual patient needs.

Lilly's testing of products from compounding pharmacies and telehealth networks identified significant impurity levels in all samples tested, raising concerns over unknown effects on health. Lilly has informed the FDA of its findings, urging a national recall, while the FDA has issued warnings to companies making misleading claims about similar products.