Pharmacist's effect on digoxin usage and toxicity.

Digoxin usage and toxicity were compared in a prospective group of patients who were monitored by a pharmacist and a retrospective group for which there was no pharmacist consultation. For the prospective group, the pharmacist monitored patients and estimated the steady-state digoxin levels by the use of a nomographic method. Level greater than 2.2 ng/ml and concurrent ECG or physical signs of digoxin toxicity were communicated to the physician. For the retrospective group, digoxin levels were calculated based on data from the patients' charts. The 49 patients in the two study groups were categorized according to four levels of digoxin toxicity (ranging from "no evidence" to "probable"). The only characteristic that was significantly different between the two groups was the calculated creatinine clearance (lower for the retrospective group). The maintenance dose of digoxin and the incidence of digoxin toxicity were significantly lower in the prospective group. It is concluded that pharmacist intervention may have had an effect in reducing digoxin dosage and toxicity.