Salivary Electrolytes in the Detection of Digitalis Toxicity

Stimulated whole saliva was collected from 73 patients, 18 with the diagnosis of digitalis toxicity; 22 were nontoxic receiving digitalis and a diuretic, 17 nontoxic receiving digitalis alone, and 16 were normal subjects. Salivary potassium and calcium concentrations were significantly higher in the group with digitalis toxicity than in the nontoxic groups. Whole-saliva potassium concentrations alone identified most of the toxic patients studied. In most cases in which the salivary potassium concentration alone failed to identify digitalis toxicity, the product of potassium and calcium did. The diagnostic usefulness of the salivary electrolyte determination is not dependent on the type of digitalis preparation used. This experience with whole-saliva potassium and calcium concentrations, coupled with earlier animal work, suggests that salivary potassium and calcium analysis is a reliable, rapid and simple method of identifying patients with digitalis toxicity.