Lead poisoning is the most frequent type of metallic intoxication, and usually produces the most severe mental symptoms. It is classified by the American Psychiatric Association (1952) under brain syndromes resulting from drug or poison intoxication. Children are more frequently afflicted than adults. Child cases are usually due to chewing on lead- painted toys or eating flakes of paint from walls; adult cases, to inhalation while engaged in paint-spraying, soldering, enameling, or metal salvage operations.Early symptoms include weakness, listlessness and irritability in all victims, but children are also likely to vomit, cry continuously, and become fearful. Severe intoxication usually results in a sudden and acute delirious state involving confusion, insomnia, tremors, violent outbursts, hallucinations, and convulsions. An episode of this kind may, in some cases, be followed by coma and death. Chronic poisoning produces depression, forgetfulness, confabulation, impaired judgment, loss of self- control, and progressive mental deterioration. Children who survive lead poisoning usually suffer from irreversible brain damage and consequent mental retardation.There is no known antidote. Therapy is directed at the relief of symptoms and the elimination of lead from the body through medications that increase the output of water. See BRAIN DISORDERS.Illustrative Case: Walter F. is a twenty-six-year-old man who developed normally until age two and a half, at which time he had convulsive seizures, vomiting, and lethargy. He was hospitalized for three months and given a diagnosis of lead encephalopathy. When he returned home, the patient did not talk until he was five years old, although prior to the convulsions he had learned to talk, walk, and had developed other motor skills usual at that age. For some months, the patient showed sudden periods of crying and extreme fear reactions. The child was not admitted to public school because of his deficiencies. He remained home where he was somewhat undependable. Generally he enjoyed being with people but often he was hostile and rebellious. He spent most of his time watching television.When the patient was twenty-two, he had a series of severe seizures and some months later became increasingly moody, irritable, and difficult to manage. Shortly before his hospitalization, he had a severe ^seizure during which he injured his head and had to be hospitalized. He was restless, confused, and complained that nothing looked the same to him. At times he seemed incoherent. When he returned home, he showed wide mood swings, became increasingly belligerent and unmanageable, talked to himself, and showed a pressured speech. Since the family could not manage him, he was admitted to the psychiatric hospital.At the time of the initial examination, the patient was found to be a somewhat disorganized man who appeared younger than his age. When he came into the examining room, he was suspicious, and asked, “Well, what’s going to happen now ” During the examination the patient displayed many mannerisms, especially involving his hands. He would stop talking suddenly and scratch the left side of his face, rub the back of his head, stand up, turn around, and rub his buttocks. He was impulsive and unpredictable. For a while he would sit quietly, and then he would get up, pace the floor restlessly, or come close to the examiner and look down in a glowering and challenging way. His gait was awkward, and his face occasionally broke into a frozen, wide-mouthed, toothy smile. (Kisker, 1964).