There are many things that can cause a fever. Is their ear pain, pain with urination, vomiting? If you know the cause of the fever then you know when to be concerned. How is the fever affecting his behavior? Were it me and the fever had lasted more than 48 hours without relenting I would take the kiddo to the doctor for a visit. My pediatrican says that until they have a fever over 101 it isn't a fever, lol that is real easy for him to say. However, he does have me treat fevers above that aggressively to keep the children from getting dehydration. He told me to give the kiddos a dose of tylenol followed by a dose of motrin four hours later and rotate those every four hours if the fever returns. It generally works really well to keep their fever down and I get them to drink some gatorade and soup.
Good luck, call your doctor to at least speak with a nurse and ease your mind. It will help you at least.
