Davison P, Wardrope J
Accident and Emergency Department, Northern General Hospital, Sheffield, England.
Drug Saf. 1993 Jan;8(1):78-80. doi: 10.2165/00002018-199308010-00009.
The tricyclic antidepressants (TCAs) are commonly used in the treatment of depression and, perhaps due to the nature of the condition being treated, figure prominently in cases of deliberate overdosage, where the toxicity of amitriptyline has been well established. However, the abrupt cessation of TCA administration can also be detrimental to the patient, triggering withdrawal phenomena often characterised by an exacerbation of the symptoms for which the patient was originally treated. We present a biochemically proven case of amitriptyline withdrawal where the clinical features at presentation made it difficult to distinguish from acute toxicity. The patient's neurological signs and distended bladder suggested amitriptyline toxicity, whereas the history and signs of cholinergic hyperactivity were consistent with acute withdrawal. The diagnosis was confirmed at a later date when further history and a biochemical analysis of plasma TCA concentrations became available. Hyponatraemia may have exacerbated the condition of the patient, whether or not it was caused by amitriptyline.
三环类抗抑郁药（TCAs）常用于治疗抑郁症，或许由于所治疗疾病的性质，在蓄意过量用药的病例中显著出现，其中阿米替林的毒性已得到充分证实。然而，突然停止服用三环类抗抑郁药也可能对患者有害，引发停药现象，其特征通常是患者最初接受治疗的症状加重。我们报告一例经生化证实的阿米替林停药病例，其呈现的临床特征难以与急性中毒相区分。患者的神经体征和膀胱膨胀提示阿米替林中毒，而胆碱能活动亢进的病史和体征与急性停药相符。当获得进一步病史和血浆三环类抗抑郁药浓度的生化分析结果后，诊断在稍后得以证实。低钠血症可能加重了患者的病情，无论其是否由阿米替林引起。
