Inhaled preparation of isoglycyrrhizic acid or salt thereof, and use in preparing drugs for treating respiratory system diseases

A method for alleviating phlegm by administrating an inhaled preparation of magnesium isoglycyrrhizinate to a subject in need thereof, characterized in that the inhaled preparation delivers the magnesium isoglycyrrhizinate to lungs to exert a local or systemic effect,

• wherein the inhaled preparation is a liquid preparation for use in a nebulizer or powder fir inhalation,
• wherein the liquid preparation for use in a nebulizer comprising magnesium isoglycyrrhizinate, sodium chloride, ammonium hydroxide, and water for injection, with the pH of 6.5-7.0, the nebulizer being a continuous nebulizer or a quantitative nebulizer, the amount of the magnesium isoglycyrrhizinate being from 0.1 mg/ml to 5 mg/ml, and the amount of the sodium chloride being 9 mg/ml;
• wherein the powder for inhalation comprises magnesium isoglycyrrhizinate and one or more pharmaceutically acceptable carriers, the magnesium isoglycyrrhizinate being micronized and has a particle size of 0.5-10 μm, and the pharmaceutically acceptable carrier being ground lactose, sieved lactose or a mixture of sieved lactose and fine lactose, the particle size distribution of the ground lactose ranging from 1 to 350 μm, the particle size distribution of the sieved lactose ranging from 1 to 200 μm and the article size distribution of the time lactose ranges being from 1 to 60 μm, the ground lactose having a particle size distribution of X50 being 30-110 μm, the sieve lactose having a particle size distribution of X50 being 35-115 μm, and the fine lactose having a particle size distribution of X90<45 μm.