Effect of epidural and subarachnoid injections of a 10% butamben suspension.

Three groups of dogs were each given repeat epidural injections of a 10% butamben suspension. A fourth group received a single subarachnoid injection of the butamben suspension. All dogs were later sacrificed and the spinal cord, meninges and spinal nerves were examined. The dogs receiving the epidural injections had no pathology. Those dogs that received subarachnoid injections had adhesive arachnoiditis. None demonstrated any evidence of neurolysis. Two cancer patients who had each received multiple injections of a 10% butamben suspension for the successful treatment of cancer pain prior to their deaths had autopsies and the spinal cords, meninges and spinal nerves were examined. No significant pathology due to the butamben was noted. Epidural butamben does not appear to cause any local tissue damage provided that subarachnoid needle placement has been ruled out. Subarachnoid butamben should be avoided.