Prodrug not its intended target. This reduces adverse or unintended effects of a drug, especially important in treatments like chemotherapy, which can have severe unintended and undesirable side effects. Many herbal extracts historically used in medicine contain glycosides (sugar derivatives) of the active agent, which are hydrolyzed in the intestines to release the active and more bioavailable aglycone. For example, salicin is a β-D-glucopyranoside that is cleaved by esterases to release salicylic acid. Aspirin, acetylsalicylic acid, first made by Felix Hoffmann at Bayer in 1897, is a synthetic prodrug of salicylic acid. However, in other cases, such as codeine and morphine,
Aristolochic acid of aristolochic acid (AA) consumption. BEN is more slowly progressive than the nephritis that is seen in CHN, but is likely caused by low-level AA exposure, possibly from contamination of wheat flour seeds by a plant of the birthwort family, "Aristolochia clematitis". CHN and BEN fall under the umbrella of what is now known as aristolochic acid nephropathy, the prevalent symptom of AA poisoning. A study reported in the Science Translational Medicine journal in October 2017 reported high incidences of liver cancer in Asia, particularly Taiwan, which bore the "well-defined mutational signature" of aristolochic acids. The same link was found