Grand mal seizures associated with high-dose intravenous morphine infusions: incidence and possible etiology.

A retrospective review of pharmacy records during a 7-year period at the Johns Hopkins Oncology Center revealed that 6 patients received greater than 4 g of morphine sulfate per day by continuous infusion (CI). Three patients received high-dose infusions for more than 24 h. Two of these 3 patients developed grand mal seizures, while the third was receiving a neuromuscular blocking agent making detection of seizures difficult.