Allopurinol cotherapy is used to improve outcomes for people with inflammatory bowel disease and Crohn's disease who do not respond to thiopurine monotherapy [REF].
Allopurinol is used as an add-on drug for refractory epilepsy, because it is an adenosine agonist, which inhibits glutamine release from excitatory neurons, but does not change the plasma concentration of other epilepsy drugs [REF].