[The rebirth of the H1-antagonists].

Anti H1s of the third generation, of which the first was Terfenadine, possess not only blocking effects on H1 receptors to histamine, but also have a "cromone-like" action on the membranes of cells that have been, or not, activated by specific stimuli (antigens). They act on the early phase of immediate hypersensitivity. These anti H1s of the new generation also have wider indications: asthma, perennial or pollen rhinitis, dermatoses such as urticaria and atopic dermatitis. Their tolerance has been remarkably improved with regard to the central effect (very reduced), such as absence of an atropine effect.