The invention relates to an effervescent pharmaceutical composition, containing metamizole sodium monohydrate, and to a method of preparing same. The effervescent dosage form has a low sodium contents, is stable during storage, has high water solubility rate without stirring, and the water solution obtained has good organoleptic properties and good quality in terms of the contents of the C impurity, the hydrolysis product of metamizole sodium. The effervescent composition is in the form of powder or granules and contains an effervescent mixture, comprising sodium carbonate and citric acid in water-free form, as well as the following excipients: water-free magnesium citrate, saccharose for direct tableting, water-free colloidal silicon dioxide, sodium cyclamate, saccharin sodium and a flavour. In order to obtain the effervescent composition, the method of roller compaction granulation is used.
