ChEBI: Sodium 2-iodohippurate is an organic sodium salt resulting from the formal reaction of equimolar amounts of 2-iodohippuric acid and sodium. It has been used as a contrast agent in urography. Isotopologues labelled with radioactive iodine were formerly used for determination of effective renal plasma flow. It has also been used labelled with radioactive iodine (iodine-125 or iodine-131) in tests of renal function and in renal imaging. It has a role as a radioopaque medium. It contains a 2-iodohippurate.