<prompt> A patient ingested some unknown substance and presented with myoclonic jerks seizures, tachycardia and hypotension.The ECG showed a hea rate of 120minute with QRS interval of 0.16 seconds. The atrial blood revealed a ph of 7.25, PCO2 of 30 mmHg and HCO3 of 15 mmolL. the most likely cause of poisoning is ingesion of-Amantia phalloidesEthylene glycolImipraminePhencyclidine  <response>: Ans. is c i.e., Imipramine CF of TCA Tricyclic Anidepressant poisoning Tricyclic antidepressant poisoning o TCAs act primarily by inhibiting serotonin and norepinephrine reuptake. It results in elevation of extracellular concentration of these neurotransmitters. o The toxic effects of TCAs are caused by four main pharmacological propeies: i Inhibition of norepinephrine reuptake at nerve terminals. ii Direct alpha adrenergic block. Anticholinergic action iv Membrane stabilizing or quinidine like effect on myocardium Clinical features o Clinical features of TCAs poisoning may be on various systems: i CNS: Seizures convulsions, drowsiness, coma, muscle spasm, rigidity, pyramidal signs, delirium, respiratory depression, ophthalmoplegia ii CVS: Tachycardia, hypotension, arrhythmias, ECG changes Prolongation of PRQRSQT interval, right axis detion, R wave greater than S wave, STT wave changes, hea block, vasodialatation, cardiogenic shock Anticholinergic: Dry mouth, blurred vision, dilated pupils, urinary retention, absent bowel sound, pyrexia iv Metabolic: Acidosis. 