Usually, the patient’s body temperature decreases about 30 minutes after taking ibuprofen orally and returns to normal in about 1 hour. Ibuprofen is mainly used for fever caused by cold. Usually, after patients take ibuprofen, it takes effect within half an hour to one hour, and the body temperature returns to normal around one hour, so the effect is faster. The effect of ibuprofen can usually be maintained for 6-8 hours, but it is not recommended to use it too early. Since fever is a self-protective measure of the body’s own immunity, a certain period of time can effectively control the rate of spread of bacteria and viruses. If applied too early, it is not conducive to controlling the spread and multiplication of bacteria and viruses, which is detrimental to human health. In addition, if the patient’s body temperature is high instead of low after taking ibuprofen orally, it is recommended to go to the hospital fever clinic for relevant examination to determine a good cause for treatment. Patients with body temperature above 38℃ are advised to take ibuprofen while taking rest and drink water appropriately to avoid getting cold and aggravating the condition.