Study of the extent and rate of bioavailability of ibuprofen tablets

The extent and rate of bioavailability of ibuprofen tablets were determined in a crossover clinical trial in 18 healthy subjects of both sexes. The study was approved by the local ethical committee and was authorized by the Spanish Medicines Agency. Volunteers signed an informed consent form and were included in accordance with the standard procedures for this type of study. In two distinct sessions participants received a single 600 mg ibuprofen dose as Gelofeno® 600 mg tablets (Laboratorios Gelos S.L.), or as the reference formulation, Neobrufen® 600 mg tablets. Ibuprofen concentrations in plasma were determined immediately before (0 h) and 0.25, 0.5, 0.75, 1, 1.5, 2, 2.5, 3, 4, 6, 8, 10, 12 and 24 h after drug administration. The pharmacokinetic parameters were then calculated. In all subjects, Gelofeno® 600 mg tablets produced plasma concentrations above the quantification limit between 15 and 30 minutes after administration, and in 9 (50%) of these subjects maximal plasma concentrations were reached at 1 h. The median tmax was 1.25 h, and the average maximal plasma concentration was 40.7 mg/l. Gelofeno® 600 mg tablets were bioequivalent both in extent and in rate of bioavailability compared with the reference drug. The formulation showed good tolerability and no medication-related adverse effects were observed. © 2005 Elsevier España S.L. Barcelona.