Possible Interaction: Monoamine Oxidase Inhibitors and Phenethylamines

“ Phenylethylamine concentrations are increased primarily by phenylalanine, its amino acid precursor and by such monoamine oxidase inhibitors as L-deprenyl and pargyline.”

“Acute pretreatment with either a Type A monoamine oxidase inhibitor MAOI ), clorgyline, or a Type B MAOI, pargyline, markedly reduced the dose of phenylethylamine (PEA) required to produce checking and a variety of other behavioral changes in rhesus monkeys.”

“These patients were generally nonresponsive to the usual treatment modalities, and their symptoms were exacerbated by nonspecific monoamine oxidase inhibitors which further increased PEA excretion rates.”

“The brain content of phenylethylamine in mice (Mosnaim and Sabelli, 1971), rabbits (Sabelli, Giardina, Mosnaim and Inwang, 1972) and rats (Fischer, Spatz, Heller and Reggiani, 1972) is increased by antidepressive treatments (imipramine, monoamine oxidase inhibitors , electroshock) and reduced by reserpine.”

“Jepson et al.3 have recently shown that administration of a monoamine oxidase inhibitor to phenylketonuric individuals results in an increase much greater than normal in the urinary excretion of phenylethylamine , but not of o-tyramine.”

“ Difluorophenylethylamine caused increased locomotor activity in mice, and its effects were enhanced by a monoamine oxidase inhibitor (tranylcypromine) as were the effects of phenylethylamine.”

“The effects of tyrosine and phenylethylamine were greatly increased by pretreatment with a monoamine oxidase inhibitor.”