Adenosine has been proposed to contribute to the pathophysiology of schizoprenia and as a
target for therapeutic intervention. In the lack of direct adenosine agonists, allopurinol may
indirectly elevate adenosine levels by inhibiting degradation of purines. We report two cases
of poorly responsive schizophrenic patients who improved considerably with add-on
allopurinol 300 mg/day. Their clear clinical improvement warrant further investigation of
allopurinol, as well as other purinergic strategies, for the treatment of schizophrenia.