Opioid use disorder: Difference between revisions

Latest revision as of 18:59, 24 October 2021

Background

A substance use disorder involving heroin, fentanyl, or other opioid medications
For reference, 1 point of street fentanyl is 100 mg, which is usually 4.4 mg of pure fentanyl

Epidemiology

The risk of OUD among patients treated with opioids for chronic pain is around 8 to 30%

Management

Precipitated withdrawal more dangerous than natural withdrawal

Acute Overdose

First give boluses of naloxone 0.04mg to 0.08mg IV to improve respiratory depression escalated quickly q2-3 minutes up to 0.4, 2, 4, 10, 15mg (start low and go fast)
Then start infusion of 2/3 the effective dose per hour
QRS and QT lengthening by blocking Na and K channels
- May need repeated defibrillation, overdrive pacing, or ECMO

Opioid Substitution Therapy (OST)

Recommend Suboxone first-line
Methadone second-line
Slow-release opioids such as Kadian third-line

Prevention

Follow safe prescribing practices
Risk assessment
- Consider their personal and family history of psychiatric illness and substance use disorder
- Consider their social history, including their living situation, safety of housing, personal safety, children or dependents, and social supports
- Can use tools such as the opioid risk tool or SOAPP-R as a more formal risk assessment
- Physical exam, looking for signs of substance use and its complications
- Bloodwork, including liver function tests, hemoglobin, and MCV

@@ Line 1: / Line 1: @@
-== Epidemiology ==
+==Background==
+*A [[substance use disorder]] involving heroin, fentanyl, or other opioid medications
-* Risk of addiction ~= 10% for non-cancer ([https://doi.org/10.1097/01.j.pain.0000460357.01998.f1 Vowles et al in Pain])
+*For reference, 1 point of street fentanyl is 100 mg, which is usually 4.4 mg of pure fentanyl
-== Management ==
+===Epidemiology===
+*The risk of OUD among patients treated with opioids for chronic pain is around 8 to 30%
-* Precipitated withdrawal more dangerous than natural withdrawal
+==Management==
-=== Acute Overdose ===
+*Precipitated withdrawal more dangerous than natural withdrawal
-* First give boluses of naloxone 0.04mg to 0.08mg IV to improve respiratory depression escalated quickly q2-3 minutes up to 0.4, 2, 4, 10, 15mg (start low and go fast)
-* Then start infusion of 2/3 the effective dose per hour
-* QRS and QT lengthening by blocking Na and K channels
-** May need repeated defibrillation, overdrive pacing, or ECMO
+===Acute Overdose===
-=== Opioid Substitution Therapy (OST) ===
+*First give boluses of naloxone 0.04mg to 0.08mg IV to improve respiratory depression escalated quickly q2-3 minutes up to 0.4, 2, 4, 10, 15mg (start low and go fast)
-* Recommend Suboxone first-line
+*Then start infusion of 2/3 the effective dose per hour
-* Methadone second-line
+*QRS and QT lengthening by blocking Na and K channels
-* Slow-release opioids third-line
+**May need repeated defibrillation, overdrive pacing, or ECMO
+===Opioid Substitution Therapy (OST)===
-==== Suboxone (buprenorphine/naloxone) ====
-* Recommended as first-line
+*Recommend [[Suboxone]] first-line
+*[[Methadone]] second-line
-* Buprenorphine is partial mu-opioid receptor agonist
+*Slow-release opioids such as [[Kadian]] third-line
-* Theoretical ceiling effect
-* Strong receptor affinity, displaces other opioids
+==Prevention==
-===== Full Start =====
+*Follow safe prescribing practices
-* Precipitates withdrawal, so wait 12-24h for short-acting, 18-36h for long-acting, or after tapering methadone
+*Risk assessment
-* Ensure COWS ≥12, then give 4mg, wait a few hours, give another 4mg
+**Consider their personal and family history of psychiatric illness and substance use disorder
-* Day 2: 12mg; Day 3: 16mg; discharge and refer to Addictions clinic
+**Consider their social history, including their living situation, safety of housing, personal safety, children or dependents, and social supports
+**Can use tools such as the [[opioid risk tool]] or [[SOAPP-R]] as a more formal risk assessment
+**Physical exam, looking for signs of substance use and its complications
+**Bloodwork, including liver function tests, hemoglobin, and MCV
-==== Methadone ====
+==Further Reading==
+*Management of opioid use disorders: a national clinical practice guideline. ''CMAJ''. 2018;190(9):e247-e257. doi: [https://doi.org/10.1503/cmaj.170958 10.1503/cmaj.170958]
-* Recommended as second-line by Canadian guidelines
+*Opioid Agonist Therapy:A Synthesis of Canadian Guidelines for Treating Opioid Use Disorder. 2021. Available at: https://www.camh.ca/-/media/files/professionals/canadian-opioid-use-disorder-guideline2021-pdf.pdf
+[[Category:Addiction medicine]]
-== Further Reading ==
-* [http://www.cmaj.ca/content/190/9/E247 Canadian Guidelines]
-[[Category:Addictions medicine]]