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Published on: December 28, 2010
Methaqualone withdrawal syndrome with photoparoxysmal responses and high-amplitude visual evoked potentials
Abstract:
Methaqualone is a sedative hypnotic that is often abused. Tolerance and habituation may develop, and the withdrawal syndrome may include seizures. In the patient studied, methaqualone withdrawal was manifested by myoclonic and tonic-clonic seizures, an EEG photoparoxysmal response (PPR), and a high-amplitude visual evoked potential (VEP) to pattern-reversal stimuli. The EEG and VEP returned to normal after resolution of the withdrawal state. Substance withdrawal should be considered in the differential diagnosis of PPR or of an unusually high-amplitude VEP in a person with no previous history of epilepsy. Disappearance of these phenomena may be a useful indicator of the end of the withdrawal state.
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