HI antihistamine

Although antihistamines have been well-known since the beginning of the cen tury and widely used since the fifties, they remain powerful medications wh ose anti-allergic and anti-inflammatory action is still useful in treatment . The first generation molecules were powerful H1 receptor antagonists but also had side effects, in particular anticholinergic and sedative. The most recent antihistamines have the advantage of being equally efficacious agai nst allergy but with little or no sedation, giving an extremely positive ri sk-benefit ratio. Their indications are: 1) allergic rhinitis, where they a re in competition with nasal steroids; 2) allergic skin diseases (at epic d ermatosis, chronic urticaria, prurigo strophulus, insect bites); 3) prevent ion of the adverse effects of immunotherapy, and 4) prevention of asthma in at-risk subjects. Clinical research on secondary prevention of asthma open s interesting perspectives, since primary prevention is complex and its eff ects inconstant. New, more powerful molecules with increased anti-inflammat ory action and even fewer side-effects should reinforce the role of antihis tamines in the treatment of allergy. (C) 2001 Editions scientifiques et med icales Elsevier SAS.