To evaluate the bioavailability of 4 different formulations of nicorandil, 10 mg and 20 mg (Bracco) versus 10 mg ang 20 mg (Merck), we have carried out a study involving 24 young healthy volunteers. The drug was administered in single oral dose and the plasma concentration levels were evaluated by HPLC method. From the results obtained, we have seen that both the 2 products of 10 mg (A and B) and the 2 products of 20 mg (C and D) are equivalent and have high relative bioavailability: it reaches the values of 96.5% (A versus B) and 120% (C versus D). As regards the 2 formulation of 20 mg, the results of bioavailability are confirmed by data obtained from dissolution study in vitro, where the dissolution is almost complete in 30 minutes.