Definition of "unmetabolized"

Unmetabolized toxines poured out of the liver upon the duodenum and probably excited at that point the secretion of hormones abnormal in character, and these stimulated abnormal secretion from the mucous glands of the stomach and bowel.

1913 July 16, “Intestinal Adhesions: Bacteriologically Experimentally and Surgically Considered”, in New York Medical Journal, volume XCVIII, number 7, page 347

The high levels of unmetabolized phenylalanine in the urine cause a very bad musty odor, which led a Norway physician to discover PKU in 1934. The unmetabolized phenylalanine also affects the brain of the child, and unless the baby is put on a special diet of no milk, meat, or other high-protein foods, the baby is doomed to severe mental retardation.

1998 May 1, “A safety net for babies”, in The Saturday Evening Post‎

Although the toxicity of inorganic arsenic is well established, arsenobetaine (from fish) is considered essentially nontoxic because it passes through the body unmetabolized; other organic forms such as dimethylarsenate, arsenolipids, and arsenosugars have uncertain toxicity.

2012 October, Matthew A. Davis et al., “Rice Consumption and Urinary Arsenic Concentrations in U.S. Children”, in Environmental Health Perspectives, volume 120, number 10, page 1418