iofendylate

Originator

Pantopaque,Lafayette,US,1944

The Uses of iofendylate

Iofendylate is a compound that is used as a contrast medium.

Indications

Iophendylate is used as a contrast agent to locate spinal tumors.

Background

Iophendylate is a mixture of isomers used as contrast medium, mainly for brain and spinal cord visualization. Iophendylate is a myelographic oil-ester (U.S. Patent 2,348,231). Iophendylate, which was never shown to be safe, was initially introduced for use in small amounts (1-2cc) for locating spinal tumors. It next appeared on the world scene for high volume (12-15cc), routine use, in diagnosing disc herniations. A number of clinicians have published on the dangers of oil myelography. In 1942 Van Wagenen (a neurosurgical colleague of Warrens, at the University of Rochester) identified Iophendylate as causing chemical meningitis in 30 patients where "space-displacing masses within the spinal canal were suspected".

Manufacturing Process

60 volumes of ethyl undecylenate is introduced gradually at 7° to 8°C during 35 minutes to a well-cooled mixture of 52.5 parts of aluminum chloride and 150 volumes of iodobenzene. The mixture is decomposed with cracked ice and dilute hydrochloric acid. The iodobenzene layer is washed with sodium bisulfite solution and with water, and then distilled. The composition of matter having the probable formula, ethyl 4-iodophenyl-undecylate, is a colorless liquid boiling at 196° to 198°C/1 mm, and of specific gravity of 1.26/20°C.

Therapeutic Function

Diagnostic aid (radiopaque medium)

Pharmacokinetics

Iophendylate is a myelographic oil-ester initially introduced for use in small amounts (1-2cc) for locating spinal tumors. Later, it was found to cause adhesive arachnoiditis. Because these substances are hyperbaric once they were placed in the subarachnoid space they would migrate to the distal portion, where they remained, producing progressive scarring.

Metabolism

Not Available