RESUMO
A 26-year-young man was taken to the hospital with symptoms of schizophrenia, and treatment began with a high dose of antipsychotic medication. After receiving medication for 3–4 days, the patient experienced persistently high body temperatures, tight muscles, and raised blood levels of CK-MB and CK-NAC. The results of all other investigations were normal. A rare Neuroleptic Malignant Syndrome (NMS) was made and treatment started with immediate withdrawal of the causative drug, and timely supportive therapy led to a successful recovery. This case illustrates the importance of adopting a broad differential diagnosis for fever, carefully reviewing the prescription lists of all patients, and taking NMS into account in patients who have both fever and stiffness.