cardiotoxicity of the tetracyclic antidepressant mianserin HCl in guinea pigs

Mianserin hydrochloride is a newly introduced antidepressant of the tetracyclic series. Unlike imipramine and other tricyclic antidepressants, mianserin was reported to be free of cardiotoxicity. In the present study the effect of the drug on the ECG pattern in anaesthetized guinea pigs was investigated in gradually increasing doses up to the toxic level. Prior to these experiments, the L.D[50] of the drug was determined in mice by the intraperitoneal route over 24 hours and 5 days. The results obtained are discussed and compared with previous findings for tricyclic drugs