The present invention relates to new salts of omeprazole and esomeprazole respectively, i.e. salts of 5-methoxy-2-[[(4-methoxy-3,5-dimethyl-2-pyridinyl)-methyl]sulfinyl]-1H-be- nzirnidazole and the (S)-enantiomer thereof. More specifically, the present invention relates to alkylammonium salts of the compounds, formed by a reaction of omeprazole and esomeprazole respectively and an alkylamine with formula NR.sub.1R.sub.2R.sub.3, wherein R.sub.1 is a linear, branched, or cyclic C.sub.1-C.sub.12-alkyl group, and R.sub.2 and R.sub.3 are hydrogen. The present invention also relates to a process for preparing crystalline salts, a pharmaceutical preparation, and a method for treatment of gastric related disorders by administering the compound of the invention.