A Prospective Survey of the Incidence of Cardiac Intoxication with Digitalis in Patients being Admitted to Hospital and Correlation with Serum Digoxin Levels

Summary: A prospective survey of the incidence of digitalis toxicity and its correlation with plasma digoxin levels determined by radioimmunoassay has failed to show any difference between plasma levels of digoxin in toxic and non-toxic patients. There was no difference in renal function or in biochemical parameters between the two groups. An irregular pulse was found more commonly in the toxic patients but otherwise symptoms and signs were the same in two groups. In view of these findings we believe levels of plasma digoxin in an individual patient may not necessarily indicate toxicity especially where there is no relationship between the time of giving the drug and taking of the blood sample.