The present invention relates to a novel process for producing transmucosal pharmaceutical formulations and to formulations thus obtained. The process relates to the preparation of grains comprising a thermolabile substance as active ingredient, and consists in dissolving said substance in a ternary mixture composed of two amphiphilic binders, the melting point of which is between 40 and 60° C., and of an aqueous solvent such as, in particular, water, an aqueous-alcoholic solution or a water-soluble solvent. The grains thus obtained comprise a thermolabile active substance, two amphiphilic binders and an inert carrier. Use in obtaining translingual tablets wherein the thermolabile active substance is adrenalin.