Comparing the toxicity of digoxin and digitoxin in a geriatric population: should an old drug be rediscovered?

BACKGROUND: Little information is available regarding toxicity rates of the two available forms of cardiac glycosides (digoxin, digitoxin) when used in elderly patients.

METHODS: We retrospectively analyzed the charts of all patients more than 60 years of age who were chronically managed with a cardiac glycoside and were hospitalized during the period January 1995 through January 1998. Toxicity was defined as any clinical event that required either a reduction in dose of the drug or its discontinuance.

RESULTS: Toxicity occurred among 7.6% of hospitalizations in which digitoxin was used, compared with 18.3% of hospitalizations in which digoxin was used. In multivariate analysis, the odds of toxicity adjusted for other clinical characteristics were three times greater for patients taking digoxin than for patients taking digitoxin.

CONCLUSION: Hospitalized elderly patients taking digitoxin had a lower rate of toxicity than those taking digoxin.