What are the different types of pain?

A report in the medical journal Annals of Internal Medicine (Mar 16, 2004) classified pain into four types: alarm (nociceptive) pain; inflammatory pain; nerve pain; and functional pain. These are described below.

Alarm (nociceptive) pain

An alarm pain indicates damage is occurring. This pain is caused by, for example, heat, cold, chemical irritants, laceration and extreme force. Stopping alarm pain during an operation or following severe trauma (eg, a car accident) is very useful. Otherwise, it is a necessary protection against damaging the body without realising it.

Inflammatory pain

Inflammatory pain follows damage to an area through injury, surgery or inflammatory diseases (eg, rheumatoid arthritis). Inflammatory pain is designed to promote healing of the injured tissue - protecting the injured area by making it very 'sensitive'. However, inflammatory pain is unhelpful in inflammatory diseases and after an operation or injury when patients need to take it easy and recover. Such people don't need to be in constant pain to remind them of that. Ideally, recovering patients should control the inflammatory pain, getting the pain sensitivity back to normal, without stopping the alarm pain mentioned above.

Nerve pain

Nerve pain is from nerve damage, such as can occur after shingles, with diabetes, following a stroke or after spinal cord injury. This pain is difficult to treat, but some medicines used for epilepsy and depression are useful.

Functional pain

Functional pain is pain sensitivity without any nerve or other abnormality being seen. This can include tension headache and fibromyalgia.

See also: Pain - what is pain? and Pain - chronic

This article was originally published in Pharmacy Today newspaper. Reviewed by everybody, June 2004.