A fever of 104?F is high and requires prompt medical evaluation. You can start with paracetamol to help lower the temperature. Mefenamic acid is a different type of medication. While these two can sometimes be used together or alternated, doing so increases the risk of side effects on your liver, stomach, and kidneys. It is safest to use just paracetamol for now, stay well-hydrated, use cool water compresses, and consult a doctor immediately. A healthcare professional will safely guide you on combining medications and diagnose the underlying cause of your fever.