Abstract: A coating agent containing 1% to 7% by mass of hydroxyalkyl cellulose, relative to the total mass of the coating agent, in which the amount of a hydroxyalkyl group, relative to the total mall of the hydroxyalkyl cellulose, is more than 50% to 60% by mass, is obtained. A solid formulation is obtained by spraying the coating agent onto a plane tablet.

Abstract: An orally disintegrating tablet is obtained by dry tabletting a mixture of: hydroxyalkyl cellulose microparticles having a 50% particle size in the cumulative particle size distribution of more than or equal to 15 ?m and less than 40 ?m, and having a hydroxyalkyl group content of 40 to 80% by mass; a main drug as a pharmaceutical ingredient; and optionally, additives such as an excipient, a binder, a disintegrant, a lubricating agent, an agent for sustained release, a base material, a coloring agent, a pH adjusting agent, a pH buffer agent, a surfactant, a stabilizer, an acidulant, a flavoring agent, a fluidizing agent, a refreshing agent, a sweetener, a savoring component, and a sweetness intensifier.

Abstract: An orally disintegrating tablet is obtained by dry tabletting a mixture of: hydroxyalkyl cellulose microparticles having a 50% particle size in the cumulative particle size distribution of more than or equal to 15 ?m and less than 40 ?m, and having a hydroxyalkyl group content of 40 to 80% by mass; a main drug as a pharmaceutical ingredient; and optionally, additives such as an excipient, a binder, a disintegrant, a lubricating agent, an agent for sustained release, a base material, a coloring agent, a pH adjusting agent, a pH buffer agent, a surfactant, a stabilizer, an acidulant, a flavoring agent, a fluidizing agent, a refreshing agent, a sweetener, a savoring component, and a sweetness intensifier.