A mucosal or cutaneous medicinal or hygiene system, comprising (a) a gas-driven foam dispenser; and (b) a fluid composition comprising (i) as the only foaming agent one or more polysaccharides, gelatins, synthetic polymers selected from the group consisting of ethylene oxide homo- and copolymers having a weight average molecular weight of at least 10,000, and homo and copolymers comprising in polymerized form acrylic acid, an acrylic acid salt, acrylamide, vinylalcohol, vinylacetate, vinylpyrrolidone or vinylpyridine, or a combination thereof; (ii) a liquid diluent, and (iii) an active ingredient for mucosal or cutaneous medicinal treatment or hygiene.