Midazolam pharmacokinetics following intravenous and buccal administration

Aims Midazolam has good anxiolytic qualities and is a well established premedication agent before anaesthesia or short surgical procedures. The objective of the present study was to determine pharmacokinetic data from individual plasma concentration profiles obtained following intravenous and buccal administration of midazolam.
Methods Eight young healthy volunteers received single doses of 5  mg midazolam i.v. and after a period of 1 week buccally in a cross over manner. Blood samples were obtained up to 480  min. The measurement of plasma midazolam concentrations was by gas-chromatography.
Results The maximum plasma concentration was 55.9  ng  ml⁻¹ (range 35.6–77.9  ng  ml⁻¹ ) at 30  min (range 15–90  min) following buccal administration. AUC was calculated to be 15 016  ng  ml⁻¹ min (s.d. 3778  ng  ml⁻¹ min) following i.v. and 11191  ng  ml⁻¹ min (s.d. 1777  ng  ml⁻¹ min) following buccal midazolam. This gave a mean midazolam bioavailabilty of 74.5%.
Conclusions The pharmacokinetic data presented in this study demonstrate a high bioavailability and reliable plasma concentrations following buccal midazolam. The clinical benefit of buccal midazolam may be in particular patient controlled premedication or sedation in adults.