PHARMACEUTICAL PREPARATION, ITS PRODUCTION AND USE OF ACIDIC ADDITIVE FOR STABILIZATION OF CILANSETRON

摘要

PROBLEM TO BE SOLVED: To obtain the subject preparation containing cilansetron stabilized against racemization by adding a specific acidic additive in an amount suitable for the stabilization of cilansetron. SOLUTION: The objective preparation contains cilansetron or its physiologically permissible acid addition salt (preferably cilansetron monohydrochloride) as an active substance at a usual dosage effective for the treatment. The preparation is produced by including at least one kind of physiologically permissible water-soluble acidic additive (preferably a 2-12C monobasic or polybasic organic acid having the 1st pKs value of 1.1-4.8, an acidic salt of the above polybasic organic acid, an acidic salt of an effective polybasic inorganic acid having the 1st pKs value of 1.5-7.5 and their mixture, e.g. ascorbic acid, its acidic salt and dihydrogen sodium phosphate) in an amount suitable for the stabilization of cilansetron against racemization.