A patient is brought to the casualty in the state of altered sensorium. He was on lithium for affective disorder and has suffered through an attack of epileptic fits. On examination he has tremors increased DTRs and incontinence of urine. He has also undergone an episode of severe gastroenteritis 2 days ago. The serum lithium was found to be 1.95 m moles/L. What is the MOST likely cause of her condition?

The clinical manifestations in this patient along with elevated levels of serum lithium more than 1.5mE/l indicates that he is suffering from lithium toxicity.Features of acute lithium intoxication includes vomiting, profuse diarrhea, coarse tremor, ataxia, coma, and convulsions. Nervous system is involved in serious cases of intoxication and its manifestations includes mental confusion, hyperreflexia, gross tremor, dysahria, seizures, and cranial nerve and focal neurological signs, progressing to coma and death.Serum levels of Lithium more than 1.5mE/L is considered to be toxic. Dialysis is the most effective means of removing Lithium in patients exhibiting symptoms of toxicity or patients with serum Li+ concentrations >/= 3 mEq/L in acute overdoses. Ref: Meyer J.M. (2011). Chapter 16. Pharmacotherapy of Psychosis and Mania. In B.C. Knollmann (Ed), Goodman & Gilman's The Pharmacological Basis of Therapeutics, 12e.