To prevent the generation of abnormality of electrolyte such as acidosis, by filling storage chambers isolated by a peel seal part, respectively with a base liquid in which an excess of negative electrolyte component is included to a positive electrolyte component within a specific range, and a bicarbonate- containing pH regulator.

An inside of a container 1 for medical use, is isolated into the storage chambers 6, 7 by an isolation seal part formed by a peal seal part. The storage chamber 7 is filled with the base liquid 3, and the storage chamber 6 is filled with a bicarbonate-containing pH regulator 4. When they are used, an isolation seal part 5 is separated and opened. In the base liquid 3, an excess of negative electrolyte component is included to a positive electrolyte component within a range of 2-35 mEg/L (excluding decomposable negative electrolyte component or positive electrolyte component). According to this composition, the stabilized condition can be kept for a long period. Further the loss of carbon dioxide can be controlled to be less than the amount of carbon dioxide for loss, generated when the pH regulator is used, even when the pH regulator is partially decomposed and the carbon dioxide is lost, whereby pH can be constantly kept, and an infusion of specific bicarbonate ion, can be obtained.