The document discusses principles and challenges of opioid rotation for cancer pain management, including calculating equianalgesic opioid doses, limitations in existing conversion charts, and case examples demonstrating rotation calculations and considerations. Opioid rotation involves switching patients to a new opioid due to issues like lack of efficacy, adverse effects, or changes in patient status, with the goal of improving pain management outcomes. Close monitoring is important when rotating opioids to safely titrate doses and manage side effects.

1. Demystifying Opioid
Rotation Calculations
#CAPhOCon17
#OpioidSwitch
Chris Ralph B.Sc. Pharm. FCAPhO
Clinical Pharmacist
Palliative Care
Complex Cancer (Pain and Symptom) Management [CCM] Service
Tom Baker Cancer Centre
Calgary, AB

2. Principles of Opioid
Use in Cancer Pain
active cancer
opioid therapy is first-line option
Moderate/Severe
Pain

3. Drug & Route Selection
● No evidence for drug-selective effects that would
uniformly justify selection of one drug over another
● Choice is empiric
● Opioid chosen typically based on:
● experience of clinician
● availability
● cost
● patient medication history
● patient clinical status

4. Opioid Rotation
● Change from one opioid to another is usually
accompanied by a better therapeutic outcome.
● Recent study:
● ~1/3 cancer pain patients underwent rotation
● benefit in > 2/3s patients
● Some studies suggest up to 80% of patients
achieve a successful outcome

5. Why Switch Opioids?
● Lack of therapeutic response
● Development of adverse effects
● Change in Patient Status
● Other Considerations
●Availability
●Cost
●Beliefs/Prior experience

6. Opioid Metaphor

7. Methadone Metaphor

8. Opioid Equianalgesic Dosing
Drug PO Dose
Morphine 10 mg
Codeine 100 mg
Tramadol* 100 mg
Oxycodone 5-7.5 mg
Hydromorphone 2 mg
Methadone** 1 mg
● Morphine is 10 times more potent than codeine
● Oxycodone is ~1.5 – 2 times more potent than morphine
● Hydromorphone is ~5 times more potent then morphine
●**Methadone conversion is variable based on total daily dose
● *tramadol maybe more potent as also inhibits reuptake of NE & 5-HT

9. Limitations of Opioid Equianalgesic Charts
● Much of the data from single-dose cross-over studies in
opioid-naïve patients with acute pain.
● Limited data on equianalgesia in chronic use
● Patient-specific variable not considered such as:
● Age, sex, ethnicity
● Polymorphism of opioid receptors
● Organ function (liver and kidney)
● Level and stability of pain control
● Duration and extent of opioid exposure
● Comorbidities
● Interacting medications
• Unidirectional Vs Bidirectional equivalences

10. Opioid Rotation
● Calculate total daily dose of current opioid
● Calc. MEDD (Morphine Equivalent Daily Dose)
● Calc. equianalgesic dose of new chosen
opioid
● *Reduce new opioid dose by 20-50%
● to account for lack of cross tolerance*
● Calculate regularly scheduled dose of new
opioid plus BT doses
● Call backs - follow up!

11. McPherson: Demystifying Opioid Conversion Calculations, 2009

13. Case: Justin Payne
60 year old man with met. prostate ca
●morphine SR 30 mg PO BID
●morphine IR (Statex) 5-10 mg PO q1h prn pain
●Taking ~ 4 x 10 mg doses per day
●Insufficient pain control
●Higher doses drowsy, confused, minor
hallucinations, myoclonus
●Plan?

14. Patient Payne Options
● Opioid-induced neurotoxicity (OIN)
● Sxs may include: delirium, myoclonus,
generalized worsening of pain
● ?Dose reduce current opioid
● (?hyperalgesia)
● Hydration
● Add an adjuvant and evaluate if it allows
for lowering of the morphine dose.
● Consider rotation to another opioid.

15. Rotation Calculation
● Morphine 60 mg (SR per day) plus 40 mg
BT/day = 100 mg/day of morphine (MEDD)
● 100 mg ÷ 5 = 20 mg hydromorphone
● 20 mg x 75% = 15 mg hydromorphone/day
● 15 mg ÷ 6 = 2.5 mg
● BT dose: 15 mg x ~10% = 1.5 mg
● Hydromorphone 3 mg po q4h (OR
Hydromorph Contin 9 mg q12h) plus 1-2
mg q1h prn

16. Payne Progression
● Now on HM Contin 9 mg po q12h for a while
but then BT use begins to increase to ~4 doses
of 2 mg per day.
● Complains of increasing drowsiness,
constipation, muscle twitching
● Wife states he seems disoriented at times.
● If she is not around he tends to forget meds.
● Rates his average pain at 4-5/10 but it
increases to 6-7/10 prior to BT doses

17. Rotating to TD Fentanyl
● Fentanyl available as 12, 25, 37, 50, 75, and 100
mcg patches
● Gel versus matrix patches
Morphine dose (oral mg/24 hr) TD fentanyl dose (mcg/hr q72h)
45-134 25
135-224 50
225-314 75
315-404 100
405-494 125
495-584 150
585-674 175
675-764 200

18. Rotating to TD Fentanyl
● Fentanyl available as 12, 25, 37, 50, 75, and 100
mcg patches
● Gel versus matrix patches
Morphine dose (oral mg/24 hr) TD fentanyl dose (mcg/hr q72h)
45-134 25
135-224 50
225-314 75
315-404 100
405-494 125
495-584 150
585-674 175
675-764 200

19. Alternate Conversion Method*
● *The conversion charts overestimate potency of
fentanyl; may lead to under-dosing
● Fentanyl: 75-100 X more potent than morphine
● 100 mg PO morphine ~ 1 mg (1000 mcg) daily TDF
● Thus 60 mg PO morphine ~ 0.6 mg (600 mcg) daily TDF
● 0.6 mg (600 mcg) daily TDF = 25 mcg per hour TDF
● Donner et al: actual ratio ~70:1
●Therefore, use a 2:1 ratio
●Every 2 mg PO morphine per day ~ 1 mcg/hour
●Thus, MEDD/2 = mcg/hr TDF

20. 2:1 Method*
● Fentanyl: 70 X more potent than morphine (Donner)
● 0.6 mg (600 mcg) daily TDF = 25 mcg per hour TDF
● 600 mcg daily TDF x 70 = 42 mg PO morphine
●42 mg PO morphine ~ = 25 mcg per hour TDF
●Therefore, use a 2:1 ratio without dose reduction
●Every 2 mg PO morphine per day ~ 1 mcg/hour
●Thus, MEDD/2 mcg/hr TDF

21. The Conversion Calculation
● HM Contin 9 mg q12h plus 4 BT/day x 2 mg/dose
= 54 mg hydromorphone/24 hr
● 26 mg x 5 = 130 mg morphine equivalents (MEDD)
1. The Chart: 130 mg 25 mcg/hr
2. Alternate: 100:1 130 = 1300 mcg ÷ 24 hr = 54.2
mcg/hr
3. 2:1 Method: 130 mg ÷ 2 = 65 mcg/hr
● Can initiate with 62 mcg and consider adjusting in
follow up.

22. Opioid Dose Escalation
*Increase by a percentage of the present dose based
upon patient’s pain rating & current assessment.
Mild pain
1-3/10
25% increase
Moderate pain
4-6/10
25-50% increase Severe pain
7-10/10
50-100% increase

23. Frequency of Dose Escalation
The frequency of dose escalation depends on the
particular opioid:
● Short-acting oral: q 2-4 hours
● Long-acting oral, except methadone:
● q 24-48 hours
● Methadone*: q 3-7 days
● transdermal fentanyl**: q 72 hours

24. ● Impeccable pain management requires
● longitudinal follow-up
● dose titration
● proactive management of adverse effects
Longitudinal Assessment

26. Suggested Resources
● McGill National Pain Centre (Opioid Guidelines in chronic non-
cancer pain, but many principles applicable to cancer pain)
● Link: http://nationalpaincentre.mcmaster.ca/guidelines.html
● The Good Stuff! (PDF: >100 pages Part B)
● Fraser Health Palliative Care Symptom Guidelines
● http://www.fraserhealth.ca/health-professionals/professional-
resources/hospice-palliative-care/
● NCI PDQ®: Supportive and Palliative Care
● http://www.cancer.gov/cancertopics/pdq/supportivecare
● Demystifying Opioid Conversion Calculations: A Guide
For Effective Dosing textbook (ML McPherson)
@ChrisRalphRx @ChrisRalphTHW

27. Contact Info
● Twitter:
● @ChrisRalphRx
● Web: http://onco-prn.blogspot.com
●New: http://bit.ly/chrisralph
● Email: cralph@ualberta.ca