Usually, diclofenac sodium relieves pain for at least 12 hours. Diclofenac sodium is a non-steroidal anti-inflammatory drug that is usually used to treat soft tissue injuries, muscle pain, osteoarthritis, sciatica and other conditions with good results. After oral administration of diclofenac sodium extended-release tablets, the drug is absorbed slowly, but the effect is maintained for a longer period of time, usually for at least 12 hours, and in some cases even for 24 hours. For mild pain, the effect is more pronounced and more effective than soothing drugs. Patients can also use hot compresses with towels to improve local blood circulation and topical ointments to invigorate blood circulation and relieve pain, for better pain relief. In addition, patients with gastrointestinal disorders should use this drug with caution because it is a strong stimulant to the stomach and can easily cause gastric bleeding or peptic ulcers.