Abstract: A composition for nasal or buccal application comprising a distribution of multilayer microparticles in an inactive base, at least one ingredient having activity on the mucosa of the nose/throat, being adsorbed within the layers of the microparticles so as to be progressively released over time in use; a method for the preparation of the composition for the controlled delivery of an active ingredient over time in situ at the mucous membranes of the nose or throat of a human, non-human mammal or other animal comprises the steps of: microencapsulating at least one ingredient having activity on the mucosa of the nose/throat within or on the layer surfaces of a multilayer microparticle; distributing the ingredient within a suitable base material serving as a means to deliver the microspheres to the active site for example suspending in a liquid base or distributing in a soluble solid base; a method of delivering an active ingredient to the nose or throat of a human, non-human mammal or other animal subject for co