Fever (pyretotherapy) was used for psychosis during the turn of the 19th century, but pyretotherapy (ie, the treatment of a disorder by inducing fever) fell out of use after the introduction of convulsive methods. Here, we report on a case of schizoaffective disorder and review classical and recent literature on fever and psychosis. The patient developed auditory hallucinations, persecutory delusional ideas, and was terrified soon upon his arrival in a foreign country. After being treated for 12 days with olanzapine and haloperidol, he developed a fever due to urinary infection; his creatine phosphokinase levels were high, prompting the suspension of antipsychotics. Psychotic symptom resolution followed immediately fever abatement. Antipsychotics were reintroduced at lower dosages. He was discharged asymptomatic with a prescription of olanzapine 15 mg/day and haloperidol 3 mg/day. The time course of symptom resolution in this patient suggests that fever had a beneficial role in this case. The associations between body temperature changes and psychotic symptoms need to be further studied.