Ibuprofen tablets usually work in about half an hour, and ibuprofen extended-release capsules usually work in 2 to 3 hours. Ibuprofen tablets belong to short-acting preparations work faster, usually within half an hour, while ibuprofen extended-release capsules belong to long-acting preparations, the onset of action time is relatively slow, usually need 2~3 hours. Ibuprofen’s onset of action may vary depending on the patient’s physical condition and disease. Ibuprofen has certain adverse reactions, such as gastrointestinal mucosal irritation, nephrotoxicity and hepatotoxicity, a few patients will also appear white blood cell decline, if the above symptoms should be as well as to communicate with the doctor, to avoid delaying the condition. It is contraindicated for those who are allergic to other NSAIDs. It is contraindicated in pregnant and lactating women. Contraindicated in patients with asthma who are allergic to aspirin. The medication should be administered under the supervision of a doctor.