Opioid Management Mark Angelo, MD, FACP Palliative Care Program
Objectives • Define where opioids are appropriate • List the two types of opioids and why the distinction is important • Using morphine as a prototype, describe how to properly administer hydrophilic opioids in the setting of chronic pain • Administer opioids properly in appropriate clinical settings
Cases • 26yo M with an abscess of the arm after a cat bite s/p I&D with mild to moderate pain, being discharged today onabx & pain control • 41yo F with severe shoulder and knee pain from mets breast cancer on morphine 600mg/day • 62yo F with SBO due to ovarian CA mets in the small intestine with severe pain and vomiting. She is allergic to morphine.
Cases • 26yo M with an abscess of the arm after a cat bite s/p I&D with mild to moderate pain, being discharged today on pain management regimen • 41yo F with breast cancer who presents with new onset shoulder and knee pain • 62yo F with SBO due to ovarian CA mets on the small intestine with severe pain and vomiting. She is allergic to morphine.
Types of Opioids Hydrophilic • Morphine • Codeine • Oxycodone • Hydromorphone • Oxymorphone Hydrophobic • Fentanyl • Methadone
Pharmacokinetics - Morphine • 1st Pass Effect – (2/3 metabolism) • Active metabolites • M-6-glucuronate (active) • M-3-glucuronate (neurotoxic) • Mostly renally excreted
Pharmacokinetics (cont’d) • T max • po ~ 1hr • sc/IM = 30 min • IV = 6 min • T ½ ~ 4h • Steady state ~ 4-5 doses
Titration • Mild –25% increase • Moderate – 50% increase • Severe – 100% increase
Chronic Pain – WHO guidelines • Basal dosing (Q day, q12hrs, q8hrs) • Breakthrough dosing - 10-20% daily dosing • Don’t forget a stimulant laxative
Kinetics - hydrophobic Fentanyl • transdermal • 13hr onset • Peak 36-48 hrs • T ½ 17hrs • Rapid acting (transmucosal) • Actiq, Fentora, Onsolis
Side Effects • Constipation • Nausea • Somnolence • Decline in mental status • Respiratory depression • Itch (histamine release) • Abuse / Diversion • Other neurotoxicity – Seizure & myoclonus
Converting the opioids • Calculate the 24hr dose of current drug. • Convert that to oral morphine equivalents (OME). • Calculate the 24hr equianalgesic dose of the new drug and reduce dose by 25-50% to allow for incomplete cross-tolerance. • Divide by the dosing schedule to achieve the correct dose. • Breakthrough dosing should be 10-20% of 24hr dose. Can be given q1-4hr prn. Exception: Fentanyl
Case 1 50-year-old elementary school teacher has breast cancer metastatic to bone. She is comfortable on a continuous infusion of morphine at 6 mg/hr. Your goal is to change to oral medications before discharging her home. What should your prescription be?
Case 2 73-year-old man with lung cancer, a malignant pleural effusion, and chronic chest pain. He has undergone therapeutic thoracentesis and pleurodesis. He is currently prescribed Dilaudid (hydromorphone) 4mg IV q 6h prn, for pain. You want to change to oral morphine. Without adjusting for cross-tolerance, what dose and schedule would you choose?
Case 3 41-year-old PCP who has ovarian cancer with ascites and has been taking 2 tablets of acetaminophen/hydrocodone (500 mg/5 mg) q4h and acetaminophen/oxycodone (325 mg/5 mg) q6h prn pain relief. What dose of hydromorphone would you choose?
Case 4 60-year-old attorney hospitalized and receiving adequate pain control with morphine 4mg/hr IV. She is now able to take nutrition and medications by mouth. Correcting 33% for incomplete cross-tolerance, what dose of oral hydromorphone would you prescribe to provide her with an approximately equal amount of analgesia? a. 2 mg poq 4h b. 4 mg poq 4h c. 8 mg poq 4h d. 12 mg poq 4h
Case 5 52-year-old male has been taking 3 Percocet 5/325 every 3 hours at home for relief of bone pain from metastatic lung cancer. He is now admitted with a neutropenic fever. You do not want him taking an antipyretic (acetaminophen). Without correcting for partial cross-tolerance, how much oral morphine elixir would you prescribe to provide analgesia similar to that which he received from the oxycodone? a. 5 mg poq 4h b. 10 mg poq 4h c. 20 mg poq 4h d. 30 mg poq 4h
Case 6 FR is a 42-year-old alcoholic with end-stage liver failure due to EtOH. He is failing in many ways and is presented with the fact that he is now going to die from his disease. Hospice is offered and he requests to go home immediately. He is currently getting dilaudid IV at 0.6mg/hr with a PCA of 0.1 which he is using rarely. He has no resources for meds and the hospice agrees to pick up his meds at no cost. What do you want to give him and what dose?
The End Mark Angelo, MD, FACP Director, Palliative Care Program Angelofirstname.lastname@example.org