Alloxan is a crystalline substance produced by oxidation of uric (by nitric acid) acid that is found in the intestine in diarrhea. Uric acid is a waste product formed from the breakdown of purines. These are substances found naturally in your body as well as in certain foods, especially organ meats — such as liver, brains, kidney and sweetbreads — and anchovies, herring, asparagus and mushrooms. Normally, uric acid dissolves in the blood and passes through the kidneys into urine. But sometimes the body either produces too much or excretes too little of this acid. Dogs with a history of prolonged exposure to toxic drugs or toxins such as alloxan have an increased risk for developing Insulin dependent diabetes mellitus (IDDM). Because it can kill the cells of the pancreas that secrete insulin, alloxan may cause diabetes.