The effects of diltiazem and metoprolol in QTc prolongation due to amitriptyline intoxication

Abstract

Background and objective: Amitriptyline, a frequently used tricyclic antidepressant agent, has powerful cardiotoxic effects especially in high doses. Serum and urine levels of amitriptyline dosages are not correlated with severity of toxicity; therefore, it increases the importance of electrocardiography (ECG) abnormalities. The prolongation of QTc can be a predictive marker for cardiotoxicity. Hence, in this study, it is aimed to evaluate possible effects of metoprolol and diltiazem in amitriptyline toxicity. Materials and methods: The rats were separated into four groups. First one was control group, the second was the amitriptyline + saline group, third one was the amitriptyline + metoprolol group, and forth one was the amitriptyline + diltiazem group. ECG were recorded on rats under anesthesia. Results: In amitriptyline group, QTc duration was prolonged compared with all other groups. The prolongation of QTc was shorter in amitriptyline + metoprolol group and amitriptyline + diltiazem group than amitriptyline group (p < 0.01 and p < 0.01, respectively). Conclusion: According to the results, it is possible to report ameliorating effects of both metoprolol and diltiazem on QTc prolongation related with amitriptyline intoxication. With further studies, these agents may be used for amitriptyline toxicity and besides, they may be used for patients in cardiovascular risk groups who take amitriptyline treatment regularly.