Effects of titration speed, gender, obesity and concomitant medications on the risk and onset time of clozapine-associated fever among Japanese patients with schizophrenia: retrospective review of charts from 21 hospitals.

A faster titration speed and concomitant treatment with valproic acid and quetiapine at clozapine initiation increased the risk of clozapine-associated fever. Clinicians should titrate clozapine with caution and consider both the titration speed and concomitant medications.