Clinical studies on the phenylethylamine hypothesis of affective disorder: urine and blood phenylacetic acid and phenylalanine dietary supplements

J Clin Psychiatry. 1986 Feb;47(2):66-70.

Abstract

To test the hypothesis that 2-phenylethylamine (PEA) modulates affect, plasma levels and urinary excretion of its main metabolite, phenylacetic acid (PAA), were studied in depressed and manic subjects, and the mood-elevating effects of its precursor, L-phenylalanine, were studied in depressed subjects. Mean total plasma PAA concentrations were 491.83 +/- 232.84 ng/ml in 12 healthy volunteers and 300.33 +/- 197.44 ng/ml in 23 drug-free patients with major depression. The 24-hour urinary PAA excretion was also measured in 48 healthy volunteers (141.1 +/- 10.2 mg PAA/24 hr) and in 144 patients with major depression (78.2 +/- 41.0 mg PAA/24 hr). The results suggest that low plasma and urinary PAA may be state markers for depression and are compatible with the PEA hypothesis. In further support, phenylalanine elevated mood in 31 of 40 depressives.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Ambulatory Care
  • Bipolar Disorder / etiology
  • Bipolar Disorder / metabolism
  • Bipolar Disorder / psychology
  • Depressive Disorder / etiology*
  • Depressive Disorder / metabolism
  • Depressive Disorder / psychology
  • Diet*
  • Emotions / drug effects
  • Female
  • Hospitalization
  • Humans
  • Male
  • Middle Aged
  • Phenethylamines / metabolism*
  • Phenylacetates / blood
  • Phenylacetates / metabolism*
  • Phenylacetates / urine
  • Phenylalanine / administration & dosage*
  • Phenylalanine / pharmacology

Substances

  • Phenethylamines
  • Phenylacetates
  • Phenylalanine