* Infectious disease, e.g. influenza, common cold, HIV, malaria, infectious mononucleosis, or
gastroenteritis
* Various skin inflammations, e.g. boils, pimples, acne, or abscess
* Immunological diseases, e.g. lupus erythematosus, sarcoidosis, inflammatory bowel diseases
* Tissue destruction, which can occur in hemolysis, surgery, infarction, crush syndrome, rhabdomyolysis, cerebral hemorrhage, etc.
* Drug fever
o directly caused by the drug, e.g.