April 01, 2016


 FDA warns makers of unapproved thyroid drugs

Posted March 16, 2016

​The Food and Drug Administration has approved one canine hypothyroidism drug and warned six manufacturers that their similar drugs were unapproved and illegal. 

Agency officials announced in late January that Thyro-Tabs Canine, from Lloyd Inc., was the first levothyroxine sodium drug approved for thyroid hormone replacement in dogs with diminished thyroid function. A separate announcement indicates the agency sent warnings that the following levothyroxine sodium products, as well as at least one similar but unnamed product, were unapproved: Leventa, Levocrine, Soloxine, Thyroid Chewable Tablets, ThyroKare, ThyroMed, Thyrosyn, ThyroVet, and Thyroxine L. 

“If a company continues to manufacture an unapproved levothyroxine product, the agency may take enforcement action, such as seizing the illegal product, filing for an injunction to prevent further sale of the product, or both,” according to a Jan. 29 letter to veterinarians, available here

The unapproved drugs are made by six pharmaceutical companies for sale under their own brands and the brands of other companies, and the names of some of those other companies have been redacted from versions of the letters provided by the FDA.

The manufacturers that received warnings are Dechra Veterinary Products, Diamond Animal Health, Merck Animal Health, Neogen Corporation, Quality Animal Care Manufacturing, and Virbac Animal Health. The letter to Neogen indicates the prohibition also applies to an unnamed similar product the company manufactures for MWI Veterinary Supply Co., and purchaser names are redacted from letters to Neogen, Quality Animal Care Manufacturing, and Virbac Animal Health.