Ibuprofen usually works 0.5 to 2 hours after use. However, the exact time of effect varies from person to person. Ibuprofen is a non-steroidal anti-inflammatory drug that can inhibit the enzyme cyclo-oxygenase, reduce the synthesis of prostaglandins, and provide antipyretic, analgesic and anti-inflammatory effects. Clinically ibuprofen is used to relieve pain from a variety of causes and fever from the common cold. In addition, gastrointestinal reactions are the most common adverse reactions to ibuprofen, which tends to irritate the intestines with nausea and vomiting, and is recommended to be taken after meals. Some patients may experience neurologic symptoms such as drowsiness and vertigo. This drug is contraindicated in patients who are allergic to aspirin or other NSAIDs. It is recommended that patients who need this drug need to take it correctly under the guidance of a doctor to avoid adverse effects.