Cardiac toxicity with thioridazine-tricyclic antidepressant combination.

Thioridazine-tricyclic antidepressant combination is frequently used in clinical practice. One reason for the choice of this combination may be its anticipated effectiveness in depressions which show both retarded and anxious features. Because both of these drugs have an adverse effect on cardiac repolarization, this may be a particularly hazardous combination. Two cases are presented illustrating life-threatening ventricular arrythmia in patients who have ingested both thioridazine and tricyclic antidepressants.