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 da ta from individual plasma concentration profiles obtained following in travenous and buccal administration of midazolam. Methods Eight young healthy volunteers received single doses of 5 mg midazolam i.v. and af ter a period of 1 week buccally in a cross over manner. Blood samples were obtained up to 480 min. The measurement of plasma midazolam conce ntrations was by gas-chromatography. Results The maximum plasma concen tration was 55.9 ng ml(-1) (range 35.6-77.9 ng.ml(-1)) at 30 min (rang e 15-90 min) following bucca! administration. AUC was calculated to be 15016 ng ml(-1) min (s.d. 3778 ng ml(-1) min) following i.v. and 1119 1 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 ph armacokinetic data presented in this study demonstrate a high bioavail ability and reliable plasma concentrations following buccal midazolam. The clinical benefit of buccal midazolam may be in particular patient controlled premedication or sedation in adults.