Routine Screening of Blood and Urine for Severe Anticonvulsant Reactions in Asymptomatic Patients is of Doubtful Value

On rare occasions anticonvulsant medication may cause severe or fatal toxic reactions. This position paper, approved by the Canadian Association for Child Neurology, examines the value of routine blood and urine screening to prevent catastrophic reactions in asymptomatic patients. The basic assumptions of such a screening program are faulty or unproven. Although not definitive, available studies of screening do not appear to support its value. It is recommended that routine blood and urine screening be discontinued in asymptomatic patients. Until such time as further research is able to identify patients at special risk, it is suggested that patients be carefully informed of the early symptoms of severe toxic reactions and report these immediately to a physician.