4-HO-MPMI, also known as 4-hydroxy-N-methyl-(ñ,N-trimethylene)tryptamine or as lucigenol, is a psychedelic drug of the pyrrolidinylmethylindole and cyclized tryptamine families.
The affinity (K<sub>i</sub>) of 4-HO-MPMI for the serotonin 5-HT<sub>2A</sub> receptor has been found to be 13nM. It produces psychedelic-appropriate responding in animal tests with similar potency as DOI. The drug has two enantiomers, with only the (R)-enantiomer being active.
Analogues of 4-HO-MPMI include MPMI, 5-MeO-MPMI, 5F-MPMI, CP-135,807, 4-HO-McPeT, 4-HO-pyr-T, and SN-22, among others.
4-HO-MPMI was developed by the team led by David E. Nichols from Purdue University in the late 1990s.
4-HO-MPMI is not a controlled substance in Canada as of 2025.