text: Tricyclic antidepressant (TCA) morbitity is primarily due to cardiac arrhythmias and hypotension, which become more refractory to treatment as acidosis progresses (Ann Emerg Med. 1985;14:1-9; Clin Toxicol. 2007;45:203-233; Flomenbaum N, Goldfrank L, Hoffman R, et al. Goldfrank's toxicologic emergencies. 8th ed. McGraw-Hill Companies, Inc, 2006).