Method for effectively reducing impurity content in oral solution for treating bronchial asthma

The invention relates to a method for effectively reducing the content of impurities in an oral solution for treating bronchial asthma, which is characterized by comprising the following steps of: filling a brown glass bottle with a diluted and constant-volume ketotifen fumarate solution, and filling argon above the liquid level of the ketotifen fumarate solution, the residual oxygen content above the liquid level of the ketotifen fumarate solution in the brown glass bottle is 5%-15%. According to the method for effectively reducing the content of the impurities in the oral solution for treating bronchial asthma, the content of the impurity G in the oral solution is controlled by filling the liquid level of the ketotifen fumarate oral solution with the protective gas until the residual oxygen amount is below a certain limit, the product safety is improved, and the content of the impurity G meets the requirement in the long-term/accelerated placement process. 本发明为一种有效降低某治疗支气管哮喘口服溶液中杂质含量的方法，其特征在于：将稀释定容后的富马酸酮替芬溶