Inappropriate digoxin monitoring.

The digoxin therapeutic drug monitoring service was evaluated during a 7-week period at Leeds General Infirmary. Data were collected for 88 patients who had one or more assays performed. The requesting clinician was contacted for each assay, and a questionnaire completed. Results were assessed to determine the appropriateness of the assay request and the action taken following receipt of the result. During the assessment period, 113 serum digoxin assays were requested. Data were collected for 88 (78%) of these, of which 22 (25%) were considered to have met all the criteria for an appropriate assay request and subsequent action. A total of 66 (75%) serum digoxin assays were assessed as wasted. The digoxin therapeutic drug monitoring service is used inappropriately at Leeds General Infirmary.