[The metabolism of drugs. Influence of protein-energy malnutrition].

The progress of a drug through human body depends not only on the inherent factors of the drug and on its formulation but also on individual physio pathological variations such as nutritional status. Pharmacokinetics of drug depend on 4 main stages (absorption, distribution, metabolisation and excretion) as showed by the serum concentrations curve or by renal elimination function of the time. Thanks to these curves one can deduce parameters currently in use. The mechanism of each of these stages is discussed and their modifications are studied in Protein Energy Malnutrition (P.E.M.). In the P.E.M. (especially in the case of child kwashiorkor) these pharmacokinetic parameters can be modified following perturbations in hydro-mineral balance, gastro-intestinal renal, hepatic functions, but principally following perturbations of the plasmatic proteins. Some of these diminish (R.B.P., albumin, prealbumin) and others increase (alpha glycoprotein acid, C reactive protein, haptoglobin, gamma globulins). Generally speaking the binding between a drug and plasmatic proteins is lowered increasing the non-bound drug quantity, the latter is more easily eliminated thus lowering the half-life of the drug provided the hepatic and renal functions are not too seriously damaged. Clinical consequences are discussed.