An improvement in digoxin bioavailability. Studies with soft gelatin capsules containing a solution of digoxin.

A study of relative bioavailability of two digoxin formulations was carried out on 28 healthy volunteer human subjects of both sexes. A commercial digoxin in tablet form was compared with a new commercial formulation which contains a solution of digoxin in soft gelatin capsules. The parameters investigated were: plasma levels, area under the plasma level-time curve, daily urinary excretion of digoxin and a series of polycardiographic measurements, all the parameters being evaluated in a steady-state condition (14 days of treatment). All the parameters investigated demonstrated better bioavailability in the capsules than in the tablets, the average improvement being 26.1%. The better bioavailability of digoxin capsules also resulted in more rapid and wider variations in the polycardiographic parameters.