[The influence of doxepin on the efficiancy of the human heart (author's transl)].

This work was aimed at clarifying whether the anti-depressant doxepin had a cardiodepressant action, or favoured or initiated arrhythmias and/or ventricular conduction disorders, when administered orally for 14 days at a daily dosage of 75 mg. Under doxepin therapy there was a slight increase in mean heart rate on effort in comparison to the placebo. This increase, which amounted to 2 to 6 beats per minute, was most marked among the younger patients, but had neither clinical nor statistical significance (cocaine-like effect of tricyclic psychotropic drugs). No significant changes of ECG, blood-pressure, x-ray determination of heart volume (by the method of Klepzig and Frisch), and maximum performance on the cycle ergometer were stated under doxepin therapy in comparison to the placebo. On the basis of these results it appears justified to state that administering oral doses of about 75 mg doxepin per day for moderately long periods produces no cardiotoxic side-effects.