Abstract: A radiological contrast composition for cerebrospinal myelography combining an iodo-benzamido-glucopyranose contrast agent and glucose, the glucose being in sufficient quantity to effectively compete in vivo with the contrast agent for brain hexokinase. Intrathecal coadministration of glucose with iodo-benzamido-glucopyranose contrast agents, exemplified by metrizamide, minimizes the central nervous system depression and irritation often associated with the intrathecal injection of the contrast agent alone. Metrizamide and related iodo-benzamido-glucopyranose contrast agents have been shown to interfere with brain glucose metabolism by competitive inhibition of the enzyme hexokinase. The competitive inhibition of hexokinase activity is counteracted by coadministration of a sufficient amount of glucose.