Tom Cotton demands FDA probe into illegal Chinese ingredients in US weight loss drugs

A Senate Republican is demanding the Food and Drug Administration (FDA) investigate whether illegal Chinese ingredients are making their way into weight loss drugs in the United States.

Sen. Tom Cotton, R-Ark., called on FDA Commissioner Martin Makary to probe how far unregulated and illegal Chinese active pharmaceutical ingredients have penetrated the U.S. supply chain — and whether they have ended up in popular weight loss drugs.

‘China’s access to America’s pharmaceutical supply chain presents national security risks as well as significant health risks to American patients,’ Cotton wrote in a letter to Makary first obtained by Fox News Digital.

Cotton’s concern follows recent reports from the FDA and Customs and Border Protection (CBP) that between September 2023 and January 2025, authorities intercepted 195 illegal shipments of active pharmaceutical ingredients.

He noted that the ingredients were ‘likely used in compounded weight loss medications’ that entered the U.S. market. Of those shipments, roughly 60 originated from China and Hong Kong.

‘It is estimated that as of January 2026, up to 1.5 million American patients could be using unregulated compounded weight loss medications that may contain potentially dangerous ingredients from Chinese manufacturers,’ Cotton wrote.

The ingredients are typically used in compounded versions of GLP-1 weight loss drugs that are marketed as alternatives to FDA-approved medications such as Ozempic and Wegovy.

Earlier this month, the Department of Health and Human Services announced it would refer telehealth company Hims & Hers to the Justice Department for ‘potential violations of the Federal Food, Drug, and Cosmetic Act’ over its planned sale of a compounded, non-FDA-approved weight loss drug.

Makary similarly said the FDA would ‘take decisive steps to restrict GLP-1 active pharmaceutical ingredients (APIs) intended for use in non-FDA-approved compounded drugs that are being mass-marketed by companies — including Hims & Hers and other compounding pharmacies — as alternatives to FDA-approved drugs.’

The company announced last week that it would remove its weight loss pill, billed as a cheaper alternative to Wegovy, from the market following mounting pressure from federal agencies.

Cotton acknowledged that move and called for similar investigations going forward.

‘I encourage further investigations into other entities that expose American patients to dangerous, unregulated Chinese APIs,’ Cotton wrote.