title: Pharmacological effects of medetomidine in humans.
abstract: Single i.v. doses of medetomidine have been administered to healthy male volunteers in three clinical phase I studies. After an initial open dose-finding study, double-blind, placebocontrolled designs were used. The highest dose tested was 120 micrograms. Medetomidine was well tolerated. It caused dose-dependent decreases of blood pressure (max 22/14 mmHg), heart rate (max 14/min) and cardiac output (max 21%) without subjective sensations of hemodynamic changes or other unexpected side-effects. However, a clear dose-dependent sedative effect, both subjective and objective, and a decrease in salivation was seen after single i.v. doses. Medetomidine had a powerful and dose-dependent effect in reducing noradrenaline (by a maximum of 75%) and increasing human growth hormone levels in plasma. All the observed pharmacological effects are well compatible with an alpha 2-agonistic action of the drug and resemble those seen after i.v. administration of clonidine. However, medetomidine appeared to be more potent and short-acting than clonidine.
authors.forename: H
authors.initials: H
authors.lastname: Scheinin
authors.forename: A
authors.initials: A
authors.lastname: Kallio
authors.forename: M
authors.initials: M
authors.lastname: Koulu
authors.forename: M
authors.initials: M
authors.lastname: Scheinin
mesh_terms: D000316:Adrenergic alpha-Agonists / Q000008:administration & dosage / Q000494:pharmacology*; D001143:Arousal / Q000187:drug effects; D004311:Double-Blind Method; D004341:Drug Evaluation; D006439:Hemodynamics / Q000187:drug effects; D006728:Hormones / Q000097:blood; D006801:Humans; D007093:Imidazoles / Q000008:administration & dosage / Q000494:pharmacology*; D007275:Injections, Intravenous; D008297:Male; D020926:Medetomidine; D012472:Salivation / Q000187:drug effects
chemical_list: D000316:Adrenergic alpha-Agonists; D006728:Hormones; D007093:Imidazoles; D020926:Medetomidine