Pain is both a warning signal and a disease in its own right. Pain is an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage.

Acute pain alerts the body to injury and usually subsides with healing. Chronic pain persists beyond normal healing and can involve altered nervous-system processing. Assessment uses patient report, scales, and functional impact because no objective meter exists. Causes range from inflammation and nerve injury to cancer and idiopathic conditions.

Treatment matches mechanism and includes physical methods, medications, interventional procedures, and psychological approaches. Untreated or poorly treated pain prolongs recovery and reduces quality of life. Listening carefully to the patient’s description remains the starting point of good care.

• Unpleasant sensory and emotional experience linked to tissue damage
• May be acute or chronic
• Assessed primarily by patient report
• Managed by multimodal approaches matched to cause