title: Safety of the oral methionine load test: effects on the clinical performance and laboratory tests.
abstract: BACKGROUND
  Hyperhomocysteinemia is a prothrombotic risk factor. Homocysteine is evaluated during fasting and after an oral methionine load (OML).
  
  
  OBJECTIVE
  To determine the safety of the OML test according to the general performance status and clinical laboratory tests. We studied healthy nonsmoking volunteers and patients with several thrombotic conditions. Before and after receiving an OML, blood samples were obtained to perform several laboratory tests. We also evaluated acute and subacute adverse effects and 30-day associated morbidity and mortality. Of 353 individuals, three were eliminated because they did not tolerate the OML. We studied 175 healthy individuals and 175 patients without age differences. After OML, mild to moderate clinical abnormalities were recorded in 78 subjects (22.1%): nausea (n = 69; 88.5%), dizziness (n = 13; 16.7%) and decreased or increased blood pressure (n = 8; 10.2%). Nausea always disappeared after breakfast in affected individuals. Prevalence of complications was similar in patients and controls. No patient required hospitalization and there was no mortality during the 30-day study period. In conclusion, OML test had no significant undesirable effects on the clinical status or the general laboratory tests of patients and healthy controls. Some mild and moderate symptoms associated with OML tests were observed, and OML test did not negatively affect general laboratory tests. OML test is a safe diagnostic procedure in patients with previous thrombotic events (and with the consequent associated risk factors such as diabetes mellitus or dyslipidemia) and in healthy subjects.
authors.affiliation: Unidad de Investigación Médica en Trombosis, Hemostasia y Aterogénesis, Instituto Mexicano del Seguro Social.
authors.forename: Abraham
authors.initials: A
authors.lastname: Majluf-Cruz
authors.forename: Manuel
authors.initials: M
authors.lastname: Moreno-Hernández
authors.forename: José Antonio
authors.initials: JA
authors.lastname: Alvarado-Moreno
authors.forename: Irma
authors.initials: I
authors.lastname: Isordia-Salas
authors.forename: Rodolfo
authors.initials: R
authors.lastname: Guardado-Mendoza
authors.forename: Karim
authors.initials: K
authors.lastname: Majluf-Cruz
authors.forename: Erika
authors.initials: E
authors.lastname: Coria-Ramírez
authors.forename: Jesús
authors.initials: J
authors.lastname: Hernández-Juárez
mesh_terms: D000284:Administration, Oral; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019411:Clinical Laboratory Techniques / Q000592:standards; D005260:Female; D006801:Humans; D020138:Hyperhomocysteinemia / Q000175:diagnosis*; D008137:Longitudinal Studies; D008297:Male; D008715:Methionine / Q000008:administration & dosage / Q000009:adverse effects; D008875:Middle Aged; D011446:Prospective Studies; D055815:Young Adult
chemical_list: D008715:Methionine