A 43 year-old female patient with a history of manic-depressive illness and prophylactic carbamazepine (CBZ) medication ingested a potentially lethal overdose of 20 g of the substance. Neurotoxic symptoms reached full intensity after about 24 hours. Subsequently, the patient developed a gastrointestinal atony, which proved to be refractory to treatment for several days. Moreover, there was an increase of bilirubin. Parallel to this we observed the persistence-and even intermittent re-increase--of toxic serum CBZ concentrations for one week with corresponding protracted clinical symptomatology.