Two hours after acetaminophen is taken, it will usually reduce the fever by 2 to 3 degrees F. Repeated does of the drug are often necessary because the fever will go up and down until the illness runs its course.

How often does Tylenol break a fever?

Take acetaminophen (Tylenol and others). A standard adult dose is 650 mg (two 325 mg tabs) every 4 hours or 1000 mg (two 500 mg tabs) every six hours.

Does Tylenol completely reduce fever?

Acetaminophen is a fever reducer and a pain reliever. It's not fully understood how this drug works. Acetaminophen doesn't decrease swelling or inflammation. Instead, it likely changes the way your body senses pain.