[Radioimmunoassay of serum digoxin levels. Clinical exploration (author's transl)].

This work undertakes, in a second part, the clinical exploration of 947 serum digoxin levels of 281 hospitalized patients on a cardiology ward. Our results, which coincide with those of other researchers, have led us to draw certain practical conclusions: the posology is determined first of all according to kidney function, weight and age of the patient. When the treatment is insufficient or, on the other hand, poorly tolerated, a serum digoxin level is performed permitting thus: 1) in the case of ineffective treatment: to be sure of the patient's cooperation, to increase the posology if the serum digoxin level is not in the toxic zone, to discover an eventual pharmacokinetic problem; 2) to establish the responsibility of digitalis (when there are signs of intolerance or of intoxication), in case of arrhythmia, in patients with pacemakers, when associated drugs are capable of causing similar adverse effects; 3) to better manage a digitalis treatment in a high risk patient (unstable renal function, advanced myocardial disease, chronic obstructive disease).