Adverse event associated with methionine loading test: a case report

Arterioscler Thromb Vasc Biol. 2002 Jun 1;22(6):1046-50. doi: 10.1161/01.atv.0000020400.25088.a7.


The death of a control subject after an oral load of methionine for a study of the possible relationship between homocysteine and Alzheimer's disease is reported. The subject developed postload plasma concentrations of methionine far beyond those reported previously in humans given the usual oral loading dose of methionine (100 mg/kg body wt). Her preload plasma metabolite values rule out known genetic diseases that might predispose one to unusually high methionine concentrations. The most likely explanation for these events is that the subject received a substantial overdose of methionine. The possibility that extremely high methionine concentrations may lead to severe cerebral effects is discussed, and it is recommended that any move to increase the sensitivity of the usual methionine loading test by increasing the dose of methionine either not be undertaken or be taken only with extreme care.

Publication types

  • Case Reports
  • Multicenter Study
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Administration, Oral
  • African Americans
  • Aged
  • Brain Death / blood
  • Brain Death / physiopathology
  • Disease Susceptibility / blood
  • Disease Susceptibility / chemically induced
  • Disease Susceptibility / microbiology
  • Drug Contamination
  • Drug Overdose / etiology
  • Fatal Outcome
  • Female
  • Genetic Predisposition to Disease
  • Humans
  • Hyperhomocysteinemia / blood
  • Hyperhomocysteinemia / chemically induced
  • Hyperhomocysteinemia / microbiology
  • Inactivation, Metabolic / genetics
  • Inactivation, Metabolic / physiology
  • Metabolism, Inborn Errors / genetics
  • Metabolism, Inborn Errors / physiopathology
  • Methionine / administration & dosage
  • Methionine / adverse effects*
  • Methionine / analysis
  • Methionine / blood


  • Methionine