[Chronopharmacokinetics of dexamethasone in young subjects]

Dexamethasone chronopharmacokinetics was studied in six young subjects 20 to 30 years old. The randomized cross-over study consisted of evening (11.00 p.m.) or morning (08.00 a.m.) dose separated by a period of one week. After the evening administration of the drug, only Tmax (1.77 +/- 0.74 à 11.00 p.m. and 0.99 +/- 0.64 à 08.00 a.m.) and Cmax/Tmax were higher than those determined at 08.00 a.m. This difference might be related to a cyclic variation of the absorption phase of dexamethasone. Thus, in our study, the time of administration has only a weak effect on the pharmacokinetics of dexamethasone.