[Evaluation of the use of digoxin in a primary care emergency service]

Digoxin is a widely used drug. Previous studies suggest a high prevalence of inadequate use, subtherapeutic levels and high toxicity rates. The aim of the present study was to evaluation the use of digoxin in our area. 50 consecutive patients who attended our emergency service and who were receiving digoxin on a chronic basis were prospectively evaluated. There were 37 females and males, with age 78.1 +/- 8.6 years. We found that digoxin was not indicated in 12% of cases. Only 48% had digoxin plasma levels within the therapeutic range. When plasma levels were considered in association with clinical and electrocardiographic findings, 12% of patients were undertreated and 6% had digitalis toxicity. There was no relation between the digoxin plasma level and the dosage schedule, the ECG findings, the renal function, the use of other drugs or the anthropometric data. Emphasis is made on the need to individualize digoxin therapy and to measure plasma levels in particular cases.