Definition of Pain Updated for the First Time Since 1979

After 40 years, a multi-national, multidisciplinary IASP Task Force developed a revised definition of pain that was published today in the journal, PAIN, along with the associated commentary by President Lars Arendt-Nielsen and Immediate Past President, Judith Turner. The revised definition included input from all potential stakeholders, including persons in pain and their caregivers.

The IASP Task Force crafted the revised definition, along with the six notes, to better convey the nuances and the complexity of pain in hope that it leads to improved assessment and management of those with pain.

The 2020 revised definition of pain is:

“An unpleasant sensory and emotional experience associated with, or resembling that associated with, actual or potential tissue damage,” and is expanded upon by the addition of six key notes and the etymology of the word pain for further valuable context:

Etymology: Middle English, from Anglo-French peine (pain, suffering), from Latin poena (penalty, punishment), in turn from Greek poinē (payment, penalty, recompense).

A central change in the new definition, compared to the 1979 version, is replacing terminology that relied upon a person’s ability to describe the experience to qualify as pain. The old definition read: “An unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage.” This wording was interpreted as excluding infants, elderly people, and others – even animals — who could not verbally articulate their pain, said Dr. Jeffrey Mogil, Director of the Alan Edwards Center for Research on Pain, McGill University and member of the Task Force.