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Equianalgesia Opioid Calculator: JHH Applications. Suzanne A Nesbit, PharmD, CPE Clinical Pharmacy Specialist, Pain Management Department of Pharmacy The Johns Hopkins Hospital. Patient Case.
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Equianalgesia Opioid Calculator: JHH Applications Suzanne A Nesbit, PharmD, CPE Clinical Pharmacy Specialist, Pain Management Department of Pharmacy The Johns Hopkins Hospital
Patient Case • 35 yo comes into the clinic complaining of persistent back pain. He has been taking Percocet (7.5mg oxycodone /324mg APAP) 2 tablets every 2-4 hours for his pain. He currently rates his pain 7/10. • Would you recommend any changes to his regimen? • Long acting opioid + short acting for breakthrough pain
Equianalgesia • Different dose of two opioids that approximately provide the same pain relief • convert route and drug • morphine 10mg parenterally standard • decrease dose by up to 50% in tolerant patient
Equianalgesic Conversion • usually convert to morphine equivalents • patient taking 18 Percocet (7.5mg/325mg) per day • 18 X 7.5mg = 135 mg oxycodone • 135 = 20 X = 202.5 mg oral morphine • decrease dose for incomplete cross tolerance X 30
Opioid Rotation • Unresponsiveness • Unmanageable adverse effects • Route of administration • Potency • Cost
Current Equianalgesia Tables • Single dose studies • Broad guidelines • Calculated dose reduced due to incomplete cross tolerance • Clinical status of the patient considered • Titrate and reassess
Equianalgesia Studies • Single Dose • Usually acute pain ; opioid naïve patients • Retrospective • Chart review of patients with opioid rotation • Cross-over • Stable patients on an opioid; switched to another to determine dose and analgesic effect
Dose Reduction • Large interpatient variability in potencies to opioids • Clinical status of patient: age, organ function, comorbidities, pain control • Relative potencies for chronic dosing unknown • Cross-tolerance: incomplete • start with 50%–75% of published equianalgesic dose • more if pain, less if adverse effects • Methadone • start with 10%–25% of published equianalgesic dose
Challenging Conversions • Fentanyl • Methadone • Oxycodone • Hydromorphone
Johns Hopkins Opioid Conversion Software and Applications • Floppy disc 1989 • PDAs 2002 • Tungsten Palm Version • Windows CE Version • Hopkins Opioid Program • Web-based version 2005 • www.hopweb.org • www.hopontheweb.org