VALIDATION OF PLASMA AND URINARY CANRENONE FOR DETERMINATION OF BIOAVAILABILITY OF SPIRONOLACTONE - COMPARISON OF TABLETS WITH SOLUTION SUSPENSION

  • 1 January 1977
    • journal article
    • research article
    • Vol. 15  (5) , 205-210
Abstract
A linear relationship between spironolactone dose and the levels of canrenone in plasma and urine are presented to support the use of canrenone levels as a measure of the bioavailability of spironolactone. The bioavailability of a selected batch of spironolactone 25 mg tablets was compared to that of an oral aqueous suspension of spironolactone in a separate balanced cross-over study involving 10 healthy subjects [human]. The tablets were equivalent to suspension as regards area under the plasma concentration-time curve and total urinary excretion of canrenone, the principal unconjugated metabolite of spironolactone. Peak plasma concentrations of canrenone were higher, and were attained significantly earlier, after treatment with spironolactone in suspension. Spironolactone appears to be absorbed more rapidly from the suspension. The total absorption probably did not differ between the 2 formulations.