5-Amino-1MQ (5-amino-1-methylquinolinium, also abbreviated 5-AMQ or 5A1MQ) is a small-molecule quinolinium cation that inhibits nicotinamide N-methyltransferase (NNMT), the cytosolic enzyme that methylates nicotinamide using S-adenosylmethionine (SAM). It emerged from a structure-activity study of N-methylated quinolinium, isoquinolinium, pyridinium and benzimidazolium analogues at the University of Texas Medical Branch. Published research is preclinical and comes largely from one group, several of whose authors have declared employment with or interests in Ridgeline Therapeutics. Studies have examined enzyme inhibition and selectivity, membrane permeability, cultured adipocytes and myoblasts, diet-induced obese mice, aged mouse muscle and rat pharmacokinetics.