Opioid Use Disorder

Ben Johnson

Background

• Standard of care is opioid stabilization with buprenorphine or methadone (in OUD) or other full agonist opioids (in chronic opioid therapy)

• Methadone and buprenorphine can be ordered by any physician for inpatients; buprenorphine can also now be prescribed at discharge by any physician, though methadone for OUD must be dispensed directly from a federally regulated Opioid Treatment Program (“methadone clinic”)

• Maintenance agonist therapy should be offered to every patient, with preference for an “opt- out” approach (even for uninsured patients through state grant funding)

Presentation (Withdrawal)

• Restlessness/psychomotor activation, anxiety, irritability, nausea, abdominal cramping, loose stool, diffuse musculoskeletal pain, chills, insomnia, yawning
• Pupillary dilation, piloerection, tearing, nasal congestion, diaphoresis, restless legs

Evaluation

• Due to the partial agonist mu-opioid effect of buprenorphine and high binding affinity, premature induction of buprenorphine in patients previously using full-agonist opioids rapidly induces a withdrawal state (precipitated withdrawal)

• Clinical Opioid Withdrawal Scale (COWS): quantifies severity of opioid withdrawal and allows for safer buprenorphine inductions

  • Approximates the mu opioid receptor availability to avoid premature induction and precipitated withdrawal in the setting of buprenorphine induction while also allowing for adequate treatment of withdrawal symptoms

• Asking about opioid exposure: “You’re uncomfortable. I work with a lot of people in the hospital, and some come with regular exposure to opioids from a lot of different places (their doctors, friends), should we be treating any withdrawal for you?”

Medications for Opioid Use Disorder (MOUD)

Buprenorphine

Background

• Partial agonist at the mu opioid receptor with high binding affinity

• Long half-life (24-36 hours) allows for daily dosing

• TID dosing is more effective for acute pain (as the analgesic effect is shorter-lived)

• OK to use in renal failure/HD; may reduce dose in hepatic injury or switch to monoptoduct buprenorphine (Child-Pugh Class C)

• All non-pregnant patients should receive buprenorphine-naloxone (e.g. Suboxone) formulations to mitigate risk of diversion/injection

Management

• Induction:
  • All opioid medication must be held 12+ hours prior to first buprenorphine dose (typically, this opioid-free period is overnight from 9 PM to 9 AM), and recorded COWS score > 10 to mitigate risk of precipitated withdrawal
  • 2-4 mg is given SL, monitoring for oversedation; additional 2-4 mg is given q1h up to a total of 12 mg in first day

    - Only sedation or hypopnea should prevent a full 12 mg dose o Typical starting dose: 12-16mg/day SL

• Maintenance:

  • 4-32mg SL daily; 16mg and above to suppress opioid use, 24 mg is sufficient in most cases
  • All patient on Suboxone must have a prescription at discharge and a follow-up appointment for continued outpatient treatment PSYCHIATRY
    • No DEA waiver required; any physician may prescribe buprenorphine for OUD at discharge

• Acute pain management in patients using buprenorphine:

• There is no contraindication to full-agonist opioid analgesia for breakthrough pain - If the etiology of pts pain would require opioid therapy in a non-OUD patient, do not avoid opioids; these may be used safely in the hospital
  • Peri-operative pain management: continue buprenorphine at reduced and split doses (4mg BID or TID); will prevent withdrawal and cravings, but NOT manage new pain
  • Post-operatively: Reduce opioid requirements and increase buprenorphine to home dose
  • If buprenorphine was discontinued, will require induction procedure to avoid

Methadone

Background

• Full mu opioid agonist with additional NMDA-receptor activity

• Better option for individuals who cannot tolerate the buprenorphine induction procedure or with significant chronic or escalating pain

• Long half life: 12-36 hrs

  • Limit titration to 10mg/d q7d, to prevent dose-stacking and delayed overdose
  • eg: 40 mg po qd increased to 50 mg po qd for one week prior to further titration to 60 mg po qd

• Safe in renal failure; dose reduction for hepatic injury

• Potential for QT prolongation at higher doses, warrants QTc monitoring

Management

• Induction:

  • In the hospital, start at 10 mg TID, holding doses for sedation or hypopnea
  • Lower doses if concerned for respiratory compromise or concurrent CNS depressant therapy
  • First dose cannot exceed 30 mg, and no more than 40 mg in first 24 hours; then titrate 5 mg/d q3d while admitted
    • Federally regulated titration limits

• Maintenance:

  • Must confirm dose with methadone clinic before restarting outpatient dose
  • Until then, do not give more than initial doses (30 mg in single dose, 40 mg in first 24 hours)
  • After confirming home dose, continue as single daily dose or divide if patient is experiencing an acute pain generator or has a medical reason for induction of metabolism (eg pregnancy may require split dosing in the 2^nd/3^rd trimester; medication interactions may have similar effects or require dose reduction if metabolism is inhibited)

Naltrexone

• Mu opioid antagonist

• Half-life oral ~4 hours but clinically active ~24 hrs

• IM maintains clinically effective levels up to 30 days (not available for inpatient administration)

• Only IM formulation is evidence-based to prevent return-to-use of illicit opioids, though PO formulation can be useful to introduce medication

• Can precipitate withdrawal

• Requires 7-10 days opioid abstinence prior to initiation

• If due for monthly injection while admitted, may substitute oral formulation (50mg po qd) until discharged to outpatient provider to receive injection

Additional Information - Psychosocial Interventions that complement MOUD: - Consider referral to SUD counseling, mutual help (self-help, 12-step, AA), intensive outpatient, and short- or long-term residential treatment

• Use of other drugs NOT a contraindication to MOUD; however, should encourage abstinence from other drugs during therapy (especially benzodiazepines)

• Prescribe intranasal naloxone for overdose prevention to all OUD patients discharging from hospital, regardless of MOUD status