Naproxen sodium chloride is used to relieve pain and reduce fever, especially during acute attacks. The active ingredient of the drug is naproxen, which is a non-steroidal antipyretic, analgesic and anti-inflammatory drug, and similar drugs such as ibuprofen, diclofenac and loxoprofen sodium. Naproxen sodium chloride is an allopathic drug, used for up to three days for fever reduction and up to five days for pain relief. If symptoms are not relieved, prompt medical attention is required. If naproxen preparations are taken for a long time, attention needs to be paid to monitoring for adverse reactions. The most common adverse reaction is irritation of the gastrointestinal tract, which may manifest as nausea, vomiting and stomach pain in mild cases, or gastric ulcer and gastric bleeding in severe cases, with a higher incidence in elderly patients.