XDH and Cachexia: The small number of studies that addressed the role of XO in cachexia-induced muscle wasting demonstrated that targeting XO with selective inhibitors such as allopurinol (4 and 40 mg/kg/day), oxypurinol (4 and 40 mg/kg/day), and febuxostat (5 mg/kg/day) can reduce body weight loss and skeletal muscle/heart atrophy [76–78].