The headquarters of the U.S. Food and Drug Administration in Silver Spring, Maryland, Nov. 4, 2009.

Jason Reed | Reuters

The ⁠Food and Drug ⁠Administration on Thursday proposed ​excluding the active ingredients in Novo Nordisk ‌ and Eli Lilly 's blockbuster obesity and diabetes medications from the ⁠list ⁠of drugs that outsourcing facilities can use for ​compounding in bulk.

If that proposal is finalized, the exclusion would likely limit the mass compounding — or the making of custom, often cheaper alternatives — of those medicines ​unless they appear on the FDA's ⁠drug shortage ⁠list.…