1. Crystalline microparticles consisting of a phenylalkylamine beta-adrenergic agonist, coated with a C12-C20 fatty acid in an amount of 0.2 to 2.5 wt%. The crystalline microparticles according to claim 1, wherein the beta agonist is selected from a derivative corresponding to the general formula (I): where R is CHOH or NHCOR, provided that when R is CHOH, R is always hydrogen, while when R is NHCOR, R and R can independently be hydrogen or together form a radical vinylene (-CH = CH-) or ethoxy (-CH-O -)； m is an integer from 0 to 5, preferably 0 or 5； n is an integer from 0 up to 4, preferably 0, 2 or 4； p is an integer from 0 to 2, preferably 0 or 1； A is oxygen or a bond； B is oxygen or a bond； R and R are hydrogen or methyl； or, when m is 1, n, p are 0, A and B are bonds, and R is hydrogen, R can form a methylene bridge - (CH) q- with R, where q is 1 or 2, preferably 1； R, R, R, R, and R, which are the same or different, are independently selected from the group consisting of hydrogen, hydroxyl, C-C1-6alkyl, C-C1-6 alkoxy, halogen atoms, SONH and 2-hydroxy-2-phenyl-ethylamino, and pharmaceutically acceptable salts and / or solvates. 3. The microparticles according to claim 2, where R is NHCOR, and R and R are H.4. Microparticles according to any one of paragraphs. 1-3, where the amount of C12-C20 fatty acid is from 0.5 to 2.0% of the mass. 5. The microparticles of claim 1, wherein the C12-C20 fatty acid is selected from the group consisting of lauric acid (C12: 0), myristic acid (C14: 0), palmitic acid (C16: 0), palmitoleic1. Кристаллические микрочастицы, состоящие из фенилалкиламинового бета-адренергического агониста, покрытые C12-C20 жирной кислотой в количестве, составляющем от 0,2 до 2,5% масс.2. Кристаллические микрочастицы по п. 1, где бета-агонист выбран из производного, соответствующего общей формуле (I):гдеRпредставляет собой CHOH или NHCOR,при условии, что когда Rпредставляет собой CHOH, Rвсегда представляет собой водород, при этом, когда Rпредставляет
