On August 31, 2016, the DEA published a notice that it was planning to place kratom in Schedule I, the most restrictive classification of the Controlled Substances Act. Its two primary active ingredients, mitragynine and 7-hydroxymitragynine (7-HMG), would be temporarily placed onto Schedule I on September 30, according to a filing by the DEA. The reasoning was "to avoid an imminent hazard to public safety". The DEA did not solicit public comments on this federal rule, as is normally done.

However, to date, the scheduling of kratom has not occurred based on the DEA list of controlled substances. Dozens of members of Congress, as well as researchers and kratom advocates expressed an outcry over the scheduling of kratom and the lack of public commenting. The DEA withheld scheduling at that time and opened the docket for public comments. Over 23,000 public comments were collected before the closing date of December 1, 2016, according to the American Kratom Association.