Allopurinol is used in the treatment of:
Allopurinol a xanthine oxidase inhibitor is used in the treatment of gout. By inhibiting xanthine oxidase it reduces uric acid synthesis. Ref: Essentials of Medical Pharmacology By KD Tripathi, 5th Edition, Page 191 - 2.
Osteoahritis
Gout
Rheumatoid Ahritis
Ankylosing spondylitis