Pain Medications – Rule of Threes

Individuals, whose painful conditions are managed through pharmacological and non-pharmacological interventions, may still experience instances of increased pain.³ The natural phenomenon of breakthrough pain often requires an “as needed” dose of pain medication to continue to provide effective pain management.^1,2,3 PRN medications remain a safe and effective treatment option to manage an individual’s breakthrough pain.^1,2,4

Rule of Threes

• If greater than 3 PRN doses in 24 hrs, consider scheduling around the clock^1,2
• If greater than 3 breakthrough doses in 24 hours consider titrating the dose ¹
• If greater than 3 breakthrough doses in 8 hours with minimal effect, consider immediate reassessment and contact Prescriber¹

Opioids may be ordered PRN (as needed) in situations where the person’s pain is not severe or constant.¹ Opioids for moderate to severe pain that is more constant should have opioids ordered on a fixed schedule around the clock¹. For people requiring around the clock dosing, there should also be an order for PRN opioid medication for breakthrough pain.¹  A starting breakthrough dose is typically 10% of the 24 hour total of their opioid medication and can be given as frequently as Q1H (every one hour) PRN (as needed).

References

1. Edmonton Zone Palliative Care Program, Alberta Health Services. (2013). How should opioids be ordered? In 99 Common Questions About Hospice Palliative Care: A nurse’s handbook (4th ed., pp. 34–34). 
2. https://www.fraserhealth.ca/-/media/Project/FraserHealth/FraserHealth/Health-Professionals/Professionals-Resources/Hospice-palliative-care/Sections-PDFs-for-FH-Aug31/9524-24-FH—Sym_Guide-Pain-Mgmt.pdf?sc_lang=en
3. CNO (2019). Practice Standard: Medication
4. Pasero, C., McCaffery, M. (2011). Pain Assessment and Pharmacologic Management.  Louis, MO: Mosby

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