The initial photoproduct obtained from santonin is lumisantonin. The plant is a source of the sesquiterpenoid santonin. Its dried flowerheads are the source of the vermifugic drug santonin since ancient times. A yellow coloration is developed upon exposure of santonin to light. This made the production of Santonin economically viable in India. One of the earliest photochemical studies dealt with the natural product santonin. It was reported that by 1843 candy lozenges were available in Germany which contained santonin. The structure of santonin was first correctly described by Clemo and Hayworth in 1929. "Artemisia cina" and other Old World species are the source of the antihelminthic drug, santonin. At least one modern herbal has also noted these same severe side effects of santonin. Santonin is neutral to litmus paper moistened with alcohol. Santonin dissolves in alkalies with formation of salts of this carboxylic acid. Santonin was often found as a major ingredient of patent remedies for intestinal worms. Santonin also was used in a lesser extent in treatment of atony of the bladder.