title: Absolute bioavailability of hydromorphone after peroral and rectal administration in humans: saliva/plasma ratio and clinical effects.
abstract: The absolute bioavailability of hydromorphone was investigated in eight healthy male subjects by a cross-over design (with washout period of two weeks) after intravenous (2 mg), peroral (4 mg) and rectal (3 mg) administration of hydromorphone. The use of saliva hydromorphone concentrations as a noninvasive technique in pharmacokinetic evaluation was investigated, and the clinical effects after the three routes of administration were determined. Hydromorphone has an absolute bioavailability of 51.35 +/- 29.29% and 36.33 +/- 29.60% after peroral and rectal administration, respectively. More side effects were observed after intravenous administration of hydromorphone than after rectal or peroral dosing. The saliva sampling for the hydromorphone concentration was found to be a useful noninvasive technique for the estimation of the elimination half-life of hydromorphone.
mesh_terms: D000284:Administration, Oral; D000285:Administration, Rectal; D000328:Adult; D001682:Biological Availability; D006207:Half-Life; D006801:Humans; D004091:Hydromorphone / Q000008:administration & dosage / Q000009:adverse effects / Q000493:pharmacokinetics*; D007275:Injections, Intravenous; D008297:Male; D008433:Mathematics; D012463:Saliva / Q000378:metabolism*
chemical_list: D004091:Hydromorphone