Hi Eva,
The bioavailability of spironolactone is greatly increased when taken with food, so you should try to do that when you can.
Clin Pharmacol Ther. 1986 Nov;40(5):531-6.
Influence of food on the bioavailability of spironolactone.
Overdiek HW, Merkus FW.
Abstract
Nine healthy volunteers received a single oral dose of 200 mg spironolactone, once during fasting conditions and once immediately after a standardized breakfast. Serum concentrations of spironolactone and its metabolites 7 alpha-thiomethylspirolactone, 6 beta-hydroxy-7 alpha-thiomethylspirolactone, and canrenone were determined by HPLC for 24 hours after dosing. By taking spironolactone with food, the mean AUC (0 to 24 hours) of the parent drug increased from 288 +/- 138 (empty stomach) to 493 +/- 105 ng-h/mL. The AUC (0 to 24 hours) of the three metabolites together also increased significantly from 8511 +/- 2062 (empty stomach) to 11219 +/- 2471 ng-hr/mL. The mean percent increase in AUC (0 to 24 hours) of spironolactone when it was given with food, compared with the ingestion on an empty stomach was much more pronounced than the corresponding increase of its metabolites. These observations indicate that food promotes the absorption of spironolactone and possibly decreases its first-pass metabolism.
(AUC = area under the plasma drug concentration-time curve, and reflects the actual body exposure to drug after administration of a dose of the drug and is expressed in mg*h/L.)
With kindness,
Terri