MGM-15, MGM-16 and mitragynine pseudoindoxyl: a notice of intent, not yet an order

The Drug Enforcement Administration has issued a notice of intent, published July 6, 2026, to place mitragynine pseudoindoxyl, MGM-15, and MGM-16 in Schedule I of the Controlled Substances Act — that is a notice, not an order, and nothing is scheduled yet. The notice was published July 6, 2026 [1].

For now, nothing about the legal status of these three substances has changed. They are not currently listed in any schedule under the CSA [1], and handling them is not a federal offence by reason of this docket. The notice states that the order, when issued, will impose Schedule I regulatory controls and the administrative, civil, and criminal sanctions that go with them on anyone who handles or proposes to handle mitragynine pseudoindoxyl, MGM-15, or MGM-16 [1]. It also states that the order will be published in the Federal Register on or after August 5, 2026 [1]. Check the legal status page before assuming a schedule applies.

Procedurally, the Administrator sent the required notice to HHS's Assistant Secretary for Health on December 15, 2025 [1]. HHS responded on January 20, 2026 that there were no investigational or approved new drug applications for any of the three substances [1], and raised no objection to temporary Schedule I placement [1].

Mitragynine pseudoindoxyl is a chemical rearrangement product of 7-hydroxymitragynine, and MGM-15 is a derivative of it; both have emerged on Mitragyna speciosa consumer markets in recent years [1]. Mitragynine pseudoindoxyl was first confirmed in consumer products in 2024 [1], MGM-15 in commercial products in September 2025 [1]. MGM-16 is described as a highly potent opioid sharing a pharmacological profile with the other two [1]. All three show strong affinity for the mu-opioid receptor and act as agonists there [1], and preclinical studies report analgesic effects more potent than morphine [1]. None of this establishes a human dose, onset, or duration for these three substances.

Whether and when the temporary order itself publishes will determine the actual change in law; this notice does not.

References

1. Schedules of Controlled Substances: Temporary Placement of Mitragynine Pseudoindoxyl, MGM-15, and MGM-16 in Schedule I — Federal Register