SPL Set ID: 0ca4baed-c5d8-4de4-ac17-6e5d1df15c03

Allopurinol is known chemically as 1,5-Dihydro-4 H -pyrazolo[3,4- d ]pyrimidin-4-one. It is a xanthine oxidase inhibitor which is administered orally. Its solubility in water at 37°C is 80 mg/dL and is greater in an alkaline solution. The structural formula is represented below: C 5 H 4 N 4 O M.W. 136.11 Allopurinol Tablets USP, 100 mg and 300 mg contain the following inactive ingredients: croscarmellose sodium, lactose monohydrate, magnesium stearate, microcrystalline cellulose, pregelatinized starch and sodium lauryl sulfate. Allopurinol Tablets USP, 300 mg also contain FD&C Yellow No. 6. Allopurinol structural formula