title: Effects of high-dose cancer chemotherapy on the absorption of digoxin in two different formulations.
abstract: The oral absorption of digoxin in tablet form has been reported to be reduced after cancer chemotherapy and radiation therapy because of cancer treatment-induced damage to the intestinal epithelium. We investigated possible differences in the effects of high-dose cancer chemotherapy on the relative bioavailability of digoxin administered in tablet form (Lanoxin; Burroughs Wellcome Co.) and in solution-in-capsule form (Lanoxicaps; Burroughs Wellcome Co.). Each subject received a single oral dose of either 0.5 mg Lanoxin (six subjects) or 0.4 mg Lanoxicaps (seven subjects) both before and after chemotherapy. For Lanoxin, there was a significant reduction in the AUC after chemotherapy to 54.4% +/- 35.5% (mean +/- SD) of the value before chemotherapy (P = 0.02), whereas for Lanoxicaps there was an insignificant reduction in AUC to 85.1% +/- 42.7% of the value before chemotherapy. These findings show that changes in the oral dosage formulation of digoxin from a tablet to a solution-in-capsule form can overcome the adverse effects of high-dose cancer chemotherapy on drug absorption, and suggest a similar approach may be successful for other drugs.
mesh_terms: D000042:Absorption; D000284:Administration, Oral; D000328:Adult; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D001682:Biological Availability; D002214:Capsules; D004077:Digoxin / Q000008:administration & dosage / Q000097:blood / Q000378:metabolism*; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D007700:Kinetics; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000532:radiotherapy; D011863:Radioimmunoassay; D011897:Random Allocation; D013607:Tablets
chemical_list: D000970:Antineoplastic Agents; D002214:Capsules; D013607:Tablets; D004077:Digoxin