Jornal de Bioequivalência e Biodisponibilidade

Abstrato

Bioavailability of Long Acting Capsules of Melatonin in Mexican Healthy Volunteers

Mireya López-Gamboa, Juan Salvador Canales-Gómez, Teresita de Jesús Castro Sandoval, Emmanuel Núñez Tovar, Maricela Alonso Mejía, María de los Ángeles Melchor Baltazar and José Antonio Palma-Aguirre

Melatonin is a molecule that is essentially secreted by the pineal gland. The oral bioavailability of immediate release melatonin is low, and several pharmacokinetic parameters have a high variability in C max and volume of distribution. The aim of this study was to investigate the bioavailability pro fi le of long acting melatonin in Mexicans. Twelve healthy volunteers participated into the study. After 12 hour overnight fast, subjects received a single capsule of long acting of melatonin 5 mg dose. For the pharmacokinetic analysis, blood samples were drawn at baseline, 0.25, 0.50, 0.75, 1.0, 1.25, 1.5, 1.75, 2.0, 3.0, 4.0, 6.0, 8.0, 10.0, 12.0 and 24.0 hours after dosing. The pharmacokinetic values were C max of 8.768 ± 7.043 ng/mL, T max of 2.7 ± 0.77 h, AUC 0-t of 29.814 ± 24.931 h.ng/ mL, AUC 0- ∞ of 38.537 ± 24.658 h.ng/mL, Cl of 185.293 ± 121.806 L/h, Vd of 451.370 ± 510.039 L and t ½ of 1.509 ± 0.768 h. The pharmacokinetic values of long acting melatonin of our study showed a high variability in C max , clearance, half- life time and apparent volume of distribution in Mexican volunteers, and there are consistent with the great variability reported in other populations that used the short acting melatonin.