This is an incredibly well-researched paper. All the nuance of FDA regulation around tDCS and similar devices is made clear. I’ve been picking away at trying to understand this myself, but had become extremely frustrated by the complexity and opacity of FDA jargon and legalese. Anna has collected all the relevant facts and applied them very close to home citing specific devices and situations the DIY tDCS crowd will be familiar with. Anna Wexler is the author as well of The practices of do-it-yourself brain stimulation: implications for ethical considerations and regulatory proposals (gated) . She spoke to myself and at least a handful of other reddit.com/r/tDCS contributors for that paper. In both papers she lays out a very sensible approach to regulating tDCS, or rather, not regulating it. Stating that there is already a body of relevant law stemming from various government agencies (in the U.S.) that could be called upon to regulate tDCS device use as needed.

This paper contributes to the literature on the regulation of consumer brain stimulation devices in the USA by providing a fact-based analysis of the consumer tDCS market and relevant laws and regulations. In the first section, I present a short history of the DIY tDCS movement and the subsequent emergence of DTC devices. In the second and third sections, I outline the basics of FDA medical device regulation and discuss how the definition of a medical device—which focuses on the intended use of the device rather than its mechanism of action—is of paramount importance for discussions of consumer tDCS device regulation. I then discuss how both the FDA and the courts have understood the FDA’s jurisdiction over medical devices in cases where the meaning of ‘intended use’ has been challenged. In the fourth section, I analyse the only instance of tDCS regulatory action to date, in which the California Department of Public Health (CDPH) forced a firm to recall several hundred consumer tDCS devices. Although there exists a common perception that the FDA has not been involved with the regulation of consumer tDCS devices, the California case demonstrates that the CDPH’s actions were instigated by an FDA engineer. Finally, I discuss the multiple US authorities, other than the FDA, that can regulate consumer brain stimulation devices.