Pain phase-based prescribing recommendations

• Acute pain: One to four days after a severe injury or medical condition, and up to seven days following a major surgical procedure or trauma. 
• Post-acute pain: Between four and 45 days following a severe injury, severe medical condition, or major surgical procedure or trauma. 
• Chronic pain: Pain lasting greater than 45 days after an acute event; or beyond the normal expected time of tissue healing.

Paradigm shift

The guidelines acknowledge the paradigm shift that is occurring in understanding pain, specifically the differences between the nature of acute pain and chronic pain. Chronic pain is not long-lasting acute pain, and it is increasingly understood as a chronic disease involving the central nervous system. Aligning the approach to chronic pain management with the chronic care model is likely to improve outcomes for the patient and reinforce the therapeutic relationship between the patient and provider. 

For further discussion of chronic pain read What is chronic pain? from the guidelines.