Analgesic formulations

The present invention relates to an improved process for obtaining a free-flowing, easily wettable, particulate effervescent effervescent composition comprising a core of aspirin materially surrounded by a layer containing a pharmaceutically acceptable, water-soluble coating material , characterized by the steps of: a) prepare a suspension of aspirin in an aqueous solution containing a coating material with a melting point of at least 105 degrees C, consisting of or including at least one ingredient selected from glycine, methionine, sucrose, lactose , a polymer of arabino-galactan, mannitol, inositol, sorbitol; For the preparation of the suspension, the aspirin is suspended in an aqueous solution of a wetting agent and the resulting suspension is converted into a smooth paste by adding a first portion of a quantity of the aqueous solution of the coating material and an agent. film former; the remaining amount of solution is added to the paste to form the suspension, which is fed with continuous agitation to a spray-spraying device, at an inlet temperature of between 150 and 300 degrees C; b) spray drying the suspension; The ingredients in the suspension are present in relative amounts such that particles comprising an aspirin core materially surrounded by a layer of the coating material are formed in the spray drying step.