Mouthwash in the form of a stable suspension comprising microspheres that incorporate an active ingredient

A mouthwash comprising microspheres incorporating an active ingredient wherein the microspheres are obtained in situ by adding drops of size smaller than 700 μm of an aqueous polymer dispersion (A) containing:

• a) polyacrylic acid, optionally cross-linked and optionally in the form of a salt with an alkali metal;
• and
• b) an alkali metal alginate
• to an aqueous solution (B) containing a pharmaceutically acceptable organic or inorganic salt of an alkaline earth metal able to cross-link the alginate, wherein the active ingredient (c) is contained either in polymer dispersion (A) or in aqueous solution (B) or in both dispersion (A) and solution (B).