However, it is important to keep in mind that a fever is not the only sign of a serious illness. While some children are fine with a temperature of 104, others can be deathly ill with a temperature of 101 or even without a fever or a low temperature. Whether or not your child has a fever, if he is very irritable, confused, lethargic (doesn't easily wake up), has difficulty breathing, has a rapid and weak pulse, is refusing to eat or drink, is still ill-appearing even after the fever is brought down, has a severe headache or other specific complaint (burning with urination, if he is limping, etc.), or if he has a fever and it is persistent for more than 24 to 48 hours, then you should call your pediatrician or seek medical attention immediately.
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