title: Presystemic and systemic glucuronidation of propranolol.
abstract: The relative importance of presystemic and systemic glucuronidation of propranolol was examined in normal subjects given single oral and intravenous doses of propranolol. The areas under the plasma concentration--time curves (AUCs) of propranolol glucuronide (PG), 41 +/- 15 ng . hr/ml, and propranolol, 48 +/- 15 ng . hr/ml, were of the same order after the intravenous dose (0.05 mg/kg). After oral doses of 20 and 80 mg, the AUCs of PG were 302 +/- 105 and 1,398 +/- 409 ng . hr/ml; these were 7 times the AUCs of propranolol, 44 +/- 15 and 220 +/- 38 ng . hr/ml. The time lapse to peak concentration, 1.5 to 3.0 hr, and the plasma half-life, 3.2 to 3.7 hr, were the same for PG and propranolol. These results demonstrate glucuronidation as an important determinant of propranolol bioavailability.
mesh_terms: D000284:Administration, Oral; D000328:Adult; D001682:Biological Availability; D005965:Glucuronates / Q000008:administration & dosage / Q000097:blood / Q000378:metabolism*; D006801:Humans; D007275:Injections, Intravenous; D008297:Male; D011433:Propranolol / Q000008:administration & dosage / Q000097:blood / Q000378:metabolism*
chemical_list: D005965:Glucuronates; D011433:Propranolol