After an introductory account on the classification of mineral waters for their use in comprehensive spa treatment the authors present findings on the hydrogeological origin and occurrence of natural bicarbonate mineral waters in the Czech Republic. They discuss in detail the main effects of drinking cures of natural sodium bicarbonate mineral waters on the gastrointestinal tract, on metabolism, the kidneys and efferent urinary pathways and the effects calcium-magnesium mineral bicarbonate waters on the gastrointestinal tract, their post-reabsorption effect on the electrolyte metabolism, kidneys and efferent urinary pathways. They mention the main indications, contraindications of drinking cures and their dosage. There is a brief paragraph on their use for inhalations. The authors describe briefly the effects of free carbon dioxide present in these waters.

        Key words: natural sodium, calcium-magnesium bicarbonate mineral waters, genesis, prevalence, drinking cure, main effects, indications, contraindications, dosage