The FDA hit Brea, California manufacturer Carolina Liquid Chemistries with a warning letter for distributing devices without premarket approval.

The company’s Class I and II in-vitro diagnostic reagent kits for tapentadol, zolpidem, spice and fentanyl, were deemed misbranded and adulterated by the agency because the company had no approved applications for the products.

The agency also noted a lack of evidence that the firm’s customers used the devices solely for forensic use and research and development uses, as required by their instructions for use. Customers included a pain management center and a clinical testing lab.