Opioid Use Disorder

Opioid Withdrawal

• clinical manifestations
  • yawning
  • sniffing, lacrimation, rhinorrhea
  • goosebumps
  • mydriasis

Opioid Agonist Therapy

Buprenorphine

Buprenorphine is a competitive partial opioid agonist used in the treatment of opioid use disorder via chronic maintenance therapy (similar to methadone maintenance therapy).

Sometimes combined with naloxone (anti-abuse mechanism) which doesn't really absorb through the GI tract (as opposed to methylnaloxone)

Buprenorphine Maintenance

When admitted to hospital, continue the same outpatient dose if the last known dose was within 3-4 days. If greater than this, involve addictions and consider dose reduction initially.

Buprenorphine Induction

Indications

• Adequate withdrawal to tolerate withdrawal: Use the COWS score to show moderate withdrawal or worse (COWS 13 and above).
• need to know the last dose of opioid taken

Contraindications

• Actively intoxicated --> can precipitate acute withdrawal as this is a partial opioid receptor agonist.
• Partial contraindication - be wary of methadone users - too long half-life, fentanyl (context-sensitive half-life).

Procedure

1. Give suboxone SL (2-4 mg, 1-2 tablets). Measure COWS in 1 hour to see if there has been a response (decreased).
2. Continue re-dosing them throughout the night.
3. End-point: once they feel comfortable!

Methadone Maintenance Therapy