Time-based descriptors of pain

Acute pain lasts less than 3 months and usually has a nociceptive component (see Pain types). It can be transient and resolve quickly without the need for medical management (eg scrapes and bruises) and can teach the body awareness (eg change posture to prevent harm). Acute pain can also be complex from the outset (eg spinal cord injury) and may persist; see The transition from acute to chronic pain.

Recurrent pain (also referred to as episodic pain) occurs episodically over 3 months or more. Each episode is similar in presentation—it may be recurrent acute nociceptive pain (eg inflammatory bowel disease) or episodes of a chronic pain condition (eg abdominal pain, migraine, back pain).

Chronic pain (also referred to as persistent pain) lasts for more than 3 months. While it may be associated with a pathology (eg arthritis, cancer, spinal cord injury), often the pathology is no longer present but pain persists because of central sensitisation.