FIELD : medicine; pharmaceuticals.SUBSTANCE : group of inventions relates to the field of medicine and chemical-pharmaceutical industry, specifically to a method for increasing the supply of lansoprazole to the bloodstream of a mammal when administered orally, comprising orally administering said mammal a solution of lansoprazole in the presence of 2R-dodecyl-2-(N, N-dimethylamino)-propionate or a salt thereof, having an enantiomeric purity of at least 70?%, to a pharmaceutical solution for oral administration, containing lansoprazole in a mixture with 2R-dodecyl-2-(N, N-dimethylamino)-propionate or a salt thereof, and a mixture of lansoprazole and 2R-dodecyl-2-(N, N-dimethylamino)-propionate or a salt thereof.EFFECT : group of inventions provides an increase in the intake of lansoprazole in the bloodstream of a mammal when administered orally.12 cl, 1 dwg, 1 tbl, 2 ex