L'insuline par voie inhalée : un modèle pour l'absorption systémique pulmonaire ?

European Union has recently approved a form of insulin intended to be inhaled. This innovative presentation has the potential to partially or completely replace the injections and thus facilitate starting insulin therapy which is considered with apprehension and too often differed. On this occasion, we reviewed the issues raised by this pulmonary route for systemic absorption (anatomical and cytological limits, cellular mechanisms, relevant physical parameters, facilitating chemical cofactors, role of tobacco smoking and of common respiratory diseases). The pharmacokinetics of inhaled and injectable insulins are comparable, apart from an appreciably faster absorption of the former and both show the same intra-individual variability. The total biodisponibility is definitely lower with the inhaled way but it is notably increased in smokers. These characteristics can vary according to the inhalation system used. A frequent induced cough, the increase in circulating anti-insulin antibodies and a potentially higher cost are not really determining obstacles. The indications will have to be clearly specified and the long-term inocuity of long term inhalation of such a mitogene especially in children and former smokers remains to be formally proven.