Pain LOs

• What adverse effect is the leading cause of death in opioid overdose

  Respiratory depression which is caused by decreased sensitivity to CO2
• Approach to address constipation

  1. Softener + Laxative like Docusate + Senna
  2. Titrate to effectiveness w/ goal of BM at least q2-3 days
  3. Avoid bulk-forming laxative if PO fluid intake < 2 liters/day
  4. If pain controlled, consider dosage reduction or opioid rotation
• Approach to adress opioid allergies

  1. Doxepin 10 mg QD-BID, emollient lotions
  2. Greatest w/ morphine so consider switching to equianalgesic dose of different opioid
• Approach to address respiratory depression

  1. This is NOT an expected side effect
  2. Data supports large doses of opioids adequate to relieve pain do not hasten death
• Approach to address nausea/vomiting

  Metoclopramide (DOC) 10 mg ACHS or Haloperidol 0.5 mg PO Q4
• Approach to address opioid induced neurotoxicity

  1. M.C occurs w/ morphine (d/t morphine 3 glucuronide metabolite) and hydromorphone
  2. Most likely to occur in patients w/ renal insufficiency, dehydration, elderly, or with concurrent use of benzodiazepines or TCAs
  3. S/sx: delirium, myoclonus, hallucinations, seizures, hyperalgesia
  4. Switch to structurally dissimilar opioid, hydration, sx control
• Approach to calculating a patient's dose of an opioid when switching from one opioid to another

  1. To account for incomplete cross-tolerance when converting a new opioid, start w/ 50-75% of equianalgesic dose of new opioid and titrate to effectiveness
  2. Dosing adjustments for renal or hepatic insufficiency, cytochrome P450 drug interactions, genetics, and other conditions or medications that affect drug metabolism, kinetics, or response may also be necessary
• Treatment of somatic and visceral pain

  1. Step 1: Non-opioids → acetaminophen, NSAIDs, Aspirin
  2. Step 2: Non-opioids + low risk/weak opioid → Acetaminophen/Hydrocodone aka Norco, Hycet, Lortab, Lorcet
  3. Step 3: Pure opioids → Morphine, Oxycodone, Hydromorphone
• Treatment of bone pain

  Use anti-inflammatory analgesics

  1. 1st line → NSAIDs (Ibuprofen, Celebrex, Ketorolac)
  2. 2nd → corticosteroids
  3. Can also use opioid in conjunction w/ anti-inflammatory
  4. Other option: bisphosphonates
• Treatment of neuropathic pain

  1. Both systemic and topical can be effective
  2. TCAs: nortriptyline (less side effects, m.c), desipramine, doxepin, amitriptyline, imipramine, duloxetine
  3. Antiepileptic: gabapentin and pregabalin common, carbamazepine, oxcarbazepine, divalproex, valproic acid
  4. Opioids, Tramadol, Lidocaine
  5. Topical: capsaicin cream or solution
• Treatment of muscle spasms/pain

  1. Skeletal muscle relaxants → Cyclobenzaprine, Baclofen, Tizanidine
  2. Benzodiazepines