Deprenyl administration in man: a selective monoamine oxidase B inhibitor without the 'cheese effect'

Psychopharmacology (Berl). 1978 Apr 14;57(1):33-8. doi: 10.1007/BF00426954.


After pretreatment with the selective monoamine oxidase B inhibitor, (-)-deprenyl, in doses sufficient for complete inhibition of the platelet enzyme, 4 normal and 6 parkinsoniam volunteers (2 receiving levodopa and 2 levodopa plus carbidopa) suffered no adverse pressor reaction ('cheese effect') after challenge with oral tyramine in amounts considerably greater than those likely to be encountered in a normal diet. Nor did the levodopa-deprenyl combination itself result in a pressor response. Normal human intestinal mucosa was shown predominantly to contain the deprenyl-insensitive A form of the enzyme, which presumably degraded administered tyramine in the deprenyl-treated volunteers; even those receiving the drug for prolonged periods manifested no 'cheese effect', suggesting that the A form remained uninhibited. Intestinal monoamine oxidase A was able to oxidise dopamine, whereas in human platelet or striatum the amine is a monoamine oxidase B substrate. Like tyramine, oral phenylethylamine challenge with amounts greater than those known to be present in a normal diet similarly gave rise to no adverse reaction in (-)-deprenyl-treated subjects; the reasons for this remain to be determined.

MeSH terms

  • Adult
  • Aged
  • Blood Platelets / enzymology
  • Cheese / adverse effects*
  • Female
  • Humans
  • Hypertension / chemically induced*
  • Intestinal Mucosa / enzymology
  • Male
  • Middle Aged
  • Monoamine Oxidase Inhibitors / adverse effects*
  • Parkinson Disease / enzymology
  • Phenethylamines / adverse effects*
  • Phenethylamines / urine
  • Time Factors
  • Tyramine / pharmacology


  • Monoamine Oxidase Inhibitors
  • Phenethylamines
  • Tyramine