ZYTO Technologies, Inc. – FDA Warning Letter, Dec 13, 2022

The FDA issued a Warning Letter to ZYTO for violations observed during a December 5-13, 2022, inspection in Lindon, UT. The firm manufactures the ZYTO Hand Cradle Galvanic Skin Response (GSR) device and associated proprietary software.

The ZYTO Hand Cradle GSR and software are deemed adulterated because they are marketed for diagnosing diseases like Alzheimer's, HIV, and Parkinson's, and recommending "balancers" for specific treatments, which constitutes a major change in intended use from its cleared purpose of measuring GSR. This expanded use lacks premarket approval (PMA) or an investigational device exemption (IDE), violating 21 U.S.C. 351(f)(1)(B). The device is also misbranded under 21 U.S.C. 352(o) for failure to submit a 510(k) premarket notification for the new intended use.

Additionally, the inspection revealed Quality System (QS) regulation violations (21 CFR Part 820), rendering the devices adulterated under 21 U.S.C. § 351(h). Deficiencies include: 1. **Design Controls (21 CFR 820.30):** Failure to adequately establish procedures for design controls, including design verification and validation for the device and its software, and for the "Tower" and