The magnitude of damage to the stomach from diclofenac sodium extended-release tablets varies from person to person, and is closely related to factors such as the length of time the medication has been used, the dosage of the medication, and each person’s different physical condition, which usually results in greater damage to the stomach in patients who have been using the medication for a long period of time, with a high dosage, and have a history of gastric problems. Gastrointestinal systemic reactions caused by diclofenac sodium extended-release tablets include the common symptoms of nausea and vomiting, diarrhea and abdominal pain, dyspepsia, flatulence and loss of appetite. Rare ones include gastrointestinal bleeding, vomiting of blood and black stools, and gastritis. It is contraindicated in people who are allergic to the drug, those with severe heart failure, hepatic failure and renal failure. Co-administration with other NSAIDs should be avoided. Symptoms that can result from an overdose of this drug include vomiting, gastrointestinal bleeding, diarrhea, and dizziness and tinnitus, and in severe cases, may lead to acute renal failure or liver damage, perforated gastrointestinal ulcers, pancreatitis, stomatitis, and lingual inflammation. The drug should be used with caution in elderly patients, pregnant and lactating women. If stomach discomfort occurs after taking diclofenac sodium extended-release tablets and is not relieved, you should go to a regular hospital in time, under the guidance of the doctor’s active treatment, to avoid delaying the condition.