Our local children's hospital has been running TV spots advising parents not to medicate children to bring down a fever unless it's relatively high (I won't be more specific 'cause I don't remember the exact temp and even if I did, I'd have to look up the celsius equivalent.) Fever isn't just an annoying immune reaction like hives or a runny nose. The higher temperature makes the body a less hospitable place for many organisms. So trying to medicate away a low-grade fever is counter-productive (except in making the patient a bit easier to live with).