Uekama K, Fujinaga T, Hirayama F, Otagiri M, Yamasaki M, Seo H, Hashimoto T, Tsuruoka M
J Pharm Sci. 1983 Nov;72(11):1338-41. doi: 10.1002/jps.2600721125.
Inclusion complexes of the digitalis glycosides digitoxin, digoxin, and methyl digoxin with three cyclodextrins (alpha-, beta-, gamma-homologues) in water and in the solid state were studied by a solubility method, IR and 1H-NMR spectroscopy, and X-ray diffractometry. Solid complexes (in a molar ratio of 1:4) of the digitalis glycosides with gamma-cyclodextrin were prepared and their in vivo absorption examined. The rapidly dissolving form of the gamma-cyclodextrin complex significantly increased plasma levels of digoxin (approximately 5.4-fold) after oral administration to dogs.
