Many drugs can cause drug fever, most often through a hypersensitivity reaction. Common examples include:

Antibiotics are the most commonly implicated class. Drug fever often begins days to weeks after starting a medicine and settles after the causative drug is stopped, but fever should not be assumed to be drug-related until infection and serious reactions are assessed. Tintinalli notes that antibiotics are the class most often responsible for drug fever.

Seek urgent care if fever comes with rash, facial swelling, breathing difficulty, mouth sores, jaundice, confusion, severe muscle stiffness, or low blood pressure. Do not stop a prescribed medicine without contacting the prescriber unless you have signs of a severe allergic reaction.