Digifab is manufactured and distributed by BTG international Inc. under U.S. License No. 186. DigiFab is a sterile, lyophilized preparation of digoxin-immune ovine Fab (monovalent) immunoglobulin fragments. It is prepared by isolating the immunoglobulin fraction of the ovine serum, digesting it with papain and isolating the digoxin-specific Fab fragments by affinity chromatography. These antibody fragments have a molecular weight of approximately 46,000 Da. Each vial of DigiFab, which will bind approximately 0.5 mg digoxin, contains 40 mg of digoxin immune Fab, 75 mg (approx) of mannitol USP, and 2 mg (approx) sodium acetate USP as a buffering agent. The product contains no preservatives and is intended for intravenous administration.