Objective: The aim of this review was to compare the pharmacokinetic properties of intranasal, intravenous, and oral formulations in 3 classes of cerebroactive drugs that might be suitable for intranasal delivery—opioids, benzodiazepines, and antimigraine agents.
Methods: A search of MEDLINE, PubMed, Cumulative Index of Nursing and Allied Health Literature, EMBASE, and Cochrane Database of Systematic Reviews (dates: 1964–April 2009) was conducted for pharmacokinetic studies of drugs that might be suitable for intranasal delivery. A comparison of pharmacokinetic data was made between these 3 routes of administration.
Results: A total of 45 studies were included in this review. Most of the opioids formulated as an intranasal spray reached a Tmax within 25 minutes. The bioavailability of intranasal opioids was high; in general, >50 % compared with opioids administered intravenously. Intranasal benzodiazepines had an overall Tmax that varied from 10 to 25 minutes, and bioavailability was between 38 % and 98 % . Tmax for most intranasal antimigraine drugs varied from 25 to 90 minutes. Intranasal bioavailability varied from 5 % to 40 % .
Conclusions: This review found that intranasal administration of all 3 classes of drugs was suitable for indications of rapid delivery, and that the pharmacokinetic properties differed between the intranasal, oral, and intravenous formulations (intravenous > intranasal > oral).