24 hour 5-HIAA: An abbreviation for 5-Hydroxyindoleacetic acid. This urine test is conducted by 24-hour urine samples and is used to determine the level of serotonin in the body. More info
24 hour Catecholamines: These hormones are created by the adrenal glands located at the top of the kidneys. This test measures the amount of the hormone in the urine.