If the fever is low, it usually does not damage the brain and does not affect intelligence. If the body temperature remains above 39℃-40℃ and does not subside, it may damage brain cells, so it is necessary to subside the fever and seek medical treatment for the cause. If the body temperature does not exceed 38.5 ℃, take physical methods to cool down, commonly used are scrubbing alcohol bath or warm water bath, etc.. But if the body temperature exceeds 38.5 ℃, you must take antipyretic drugs to reduce fever. During the fever period, you must drink more water, eat a light diet, and avoid eating spicy and stimulating food.