chronic pain, pain that continues or recurs over a prolonged period (usually longer than 12 weeks), caused by various diseases or abnormal conditions. Chronic pain may be less intense than acute pain. The person with chronic pain does not usually display increased pulse and rapid respiration because these autonomic reactions to pain cannot be sustained for long periods. Some factors that can complicate the treatment of persons with chronic pain are scarring, continuing psychological stress, and medication. Compare acute pain. See also pain, pain intervention, pain mechanism.
