Bioavailability of dexmedetomidine after extravascular doses in healthy subjects

Abstract

Aim: To determine the absolute bioavailability of extravascularly administered dexmedetomidine, a novel a2-adrenoceptor agonist, in healthy subjects.

Methods: Single 2 microg x kg-1 doses of dexmedetomidine were given intravenously, intramuscularly, perorally and buccally (where the solution is not swallowed) to 12 healthy male subjects. The drug concentration-time data were analysed using linear one-compartment (buccal and peroral data), or two-compartment modelling (intravenous data), or noncompartmental methods (intramuscular data).

Results: Mean (95% CI) absolute bioavailability after peroral, buccal and intramuscular administration was 16% (12-20%), 82% (73-92%) and 104% (96-112%), respectively.

Conclusion: Dexmedetomidine is well absorbed systemically through the oral mucosa, and therefore buccal dosing may provide an effective, noninvasive route to administer the drug.

Figures

Figure 1

Mean curves of dexmedetomidine concentrations in serum vs time after intravenous (i.v), intramuscular (i.m), buccal and peroral (p.o) administration of a single 2.0 µg kg−1 dose. i.v. (▪); i.m. (□); buccal (○); and p.o. (•).