Sonicated transdermal drug transport.

The following review explores the promise shown by sonicated transdermal drug transport as a novel drug delivery system in great detail. It elucidates the advantages of transdermal drug transport (TDT) over the currently prevalent modes of drug administration and then goes on to explain why despite these obvious advantages TDT is so sparingly used. This discussion includes the problems posed by the impregnable barrier--our skin, or more precisely the stratum corneum (SC), and how sonicated TDT breaches this barrier. A succinct definition of sonophoresis is included along with a description of the experimental setup and a discussion of the results. The mechanism of sonophoresis with particular emphasis on the role of cavitation (both inside and outside the skin), thermal effects, convective transport, and mechanical stresses is also included. The paper also includes a discussion on the variation of sonophoretic enhancement from drug to drug along with a recent mathematical model explaining this. The paper concludes with a section detailing possible applications of sonicated TDT in the near future. Copyright 2002 Elsevier Science B.V.