Cyclodextrins: application in different routes of drug administration.

The objective of this review article is to explain the use of cyclodextrin in the different routes of drug administration. The article gives the chemistry of cyclodextrins and addresses the issue of the mechanism of drug release from cyclodextrin complexes. Dilution, competitive displacement, protein binding, change in ionic strength and temperature and drug uptake by tissues are the different release mechanisms of the drug from the drug-cyclodextrin complex discussed here. Use and its limitations in the different drug delivery systems like nasal, ophthalmic, transdermal and rectal drug delivery are explained. The application of the cyclodextrins in the oral drug delivery is detailed in this review. Many studies have shown that cyclodextrins are useful additives in the different routes of drug administration because of increased aqueous solubility, stability, bioavailability and reduced drug irritation.