 This may not be true for the ICU patient. Some research found acetaminophen was not as good at reducing fever as expected in the ICU. Fever helps to fight infection so it may help patients get better, but it is also stressful. When you have fever, you to need more oxygen, and your heart beats faster. If you have a fever after brain injury, you are less likely to make a full recovery. In patients with brain injury, a weak heart or trouble breathing we should treat fever. If we can predict how well acetaminophen will reduce fever, we can decide if this drug is enough, or other treatments are also needed. 