Transdermal delivery of drugs for the treatment of bone diseases

The curl ent status of transdermal drug delivery for the treatment of bone diseases is described in this review. The structure, physiology and Functio n of skin and their importance in determining delivery into and across skin are discussed. Special emphasis has been devoted to a description of the m ajor pathways: of transport across the skin and the quite continuing contro versy over the importance of the transfollicular route. An overview of anat omic site-dependent drug absorption is also provided and is particularly re levant to determination of transdermal patch location. Brief descriptions o f the criteria fur sc lection of transdermal drug candidate, transdermal pa tch designs and currently marketed transdermal products are also included. Transdermal estradiol delivery systems are examined in more derail for thei r clinical and biological effects. Finally, the feasibility of delivering d rugs such as bisphosphonates across skin is discussed. (C) 2000 Elsevier Sc ience B.V. All rights reserved.