How high can you let your temperature get before going to the emergency room?

Fever: Different individuals tolerate fever differently. You can modulate your fever with aspirin, Acetaminophen or other antipyretics, take a tepid bath, etc. Fever does not generally produce neurological changes until it exceeds 105 f, but this is only in adults. Fever alone should not necessarily drive you to go to er. You must assess other symptoms and likelihood that this is more than a virus.