Excretion of ketobemidone in human breast milk

The excretion of ketobemidone into human breast milk was investigated in three women who obtained ketobemidone as postoperative pain relief after Cesarean section and two women premedicated with 5 mg of ketobemidone before currettage after delivery. The highest observed concentration of ketobemidone in breast milk was 36 ng/ml three hours after administration, and 4-7 hours after administration the concentration was 3-5 fold that in maternal plasma. It could be estimated that the newborn will be exposed to less than 2 micrograms of ketobemidone during the first 24 hours.