Wk 26 - Opioid dependence in practice

Question 1

What is an opioid?

Answer 1

Natural derivative of opium w/ agonist + antagonist activity at opioid receptors

Question 2

Which opiate has the greatest potential for dependence?

Answer 2

Diamorphine

Question 3

When can physical + psychological dependce develop?

Answer 3

2-10 days of continuous use

Question 4

What are the complications of opioid dependence?

Answer 4

• OD
• HIV + hep
• Homelessness + crime

Question 5

What are the key elements of opioid dependence?

Answer 5

• Strong compulsion to take opioid
• Physiological w/drawal
• Tolerance
• Neglect of pleasures + interest
• Persistent use despite harmful consequences

Question 6

What is opioid dependence managed by?

Answer 6

• Opioid sub therapy

- Psychological support

Question 7

What is the aim of OST?

Answer 7

• Improve qual of life

- Red harm of using drugs

Question 8

What is the dose for methadone?

Answer 8

• Initiation: 10-30mg/day
• <20 if: tolerance uncertain/taking other sedatives
• Maintenance: 60-120mg
• Inc risk QT prolongation: >100mg

Question 9

What are the interactions of methadone?

Answer 9

• Affected by CYP450 inducers + inhibitors
• Respiratory depression by other CNS depressants
• QT prolongation

Question 10

What are the adverse effects of methadone?

Answer 10

• Clouded mind
• Opiate s/e
• QT prolongation
• Torsades de pointes

Question 11

What needs to be monitored when using methadone?

Answer 11

• BP
• Pulse
• LFTs
• U+E
• ECG

Question 12

What are the signs of QT prolongation?

Answer 12

• Palpitation
• Syncope
• Dizziness
• Lightheadedness
• > 500ms

Question 13

What is the dose for buprenorphine?

Answer 13

• Max 32mg

- Typical: 12-16mg

Question 14

What are the adverse effects of buprenorphine?

Answer 14

• Less sedating than methadone

- Hepatic necrosis

Question 15

What are the cautions + contraindications of buprenorphine?

Answer 15

• Liver dysfunction
• Hep B + C
• Hepatotoxic drugs

Question 16

Give examples of reasons to suspect opioid dependency

Answer 16

• Drug misuse: OD, HIV, poor dental care
• Intoxication: itching, lower BP, constriction of pupils
• W/drawal: watering eyes, sneezing, clammy skin, tremor, HT
• Physical: tracks, poor nutrition

Question 17

What does a drug assessment often include?

Answer 17

• History taking
• Urine drug screen
• ECG
• LFT
• U+E
• FBC
• Hep B + C + HIV

Question 18

Urine drug samples

Answer 18

• Prior to OST + every 3 months
• Heroin: 48hr
• Methadone: 7-9 days
• Buprenorphine: 1-2 wks

Question 19

What is maintenance OST?

Answer 19

• Indication: red use but not ready to come off completely

- Supervision consumption arranged for 1st 3 months

Question 20

What is detoxification?

Answer 20

• Indication: Drug free
• Takes 28 days inpatient + 12 wks community
• Initiated once stabilised on OST

Question 21

Outline the detoxification programme

Answer 21

Methadone:
- Red rate where 12 wks = 0

• Red 5mg every 1-2 wks

Buprenorphine:
- Red initially by 2mg every 2 wks

• Final red 400mcg

Question 22

Give examples of symptomatic treatment to manage withdrawal

Answer 22

• Di - Loperamide
• Nausea + vom - Metoclopramide
• Stomach pain - mebeverine
• Aches/pains - paracetamol/ibuprofen
• Agitation/anxiety - diazepam/zopiclone

Question 23

What is given during detoxification programmes to prevent relapse?

Answer 23

Naltrexone

Question 24

How is methadone maintenance initiated?

Answer 24

• Initial: 10-30mg/day
• Heavily dependent: 40mg
• No more than 5-10mg inc in 1 day
• No more than 30mg inc in 1 wk
• 3-10 days to reach steady state

Question 25

What are the risk factors for overdose on induction?

Answer 25

• Low opioid tolerance
• CNS depressant drugs
• Interactions
• Too high initial
• Rapid dose inc

Question 26

What happens in subsequent optimisation in methadone maintenance?

Answer 26

• Titrate against w/drawal symptoms
• Inc 60-120mg/day
• Inc w/ 3-5 days btw dose change

Question 27

How is buprenorphine initiated (day 1)?

Answer 27

• Start 4mg (mild-mod) to 8mg (mod-severe)
• 4mg if unknown dependency or polydrug use
• Wait 6-12 hrs after last heroin use or 24-28hr after last low-dose methadone

Question 28

What happens in day 2 of giving buprenorphine?

Answer 28

• Rapidly titrate dose
• 2mg, 4mg or 8mg
• Aim: stable effects for 24hrs
• Maintenance: 12mg to 24mg
• Max 32mg

Question 29

Which opioid is safer to initiate?

Answer 29

Buprenorphine - less over sedation, respiratory depression + OD

Question 30

What are signs of overdose?

Answer 30

• Pinpoint pupils (miosis)
• Respiratory depression
• Unresponsive
• Sedation

Question 31

What is the management for opioid toxicity?

Answer 31

Naloxone

Question 32

Buprenorphine over methadone

Answer 32

• Safer in OD
• Patient dependent on codeine + hydrocodeine
• Cease heroin use
• Less affected by inducers + inhibitors
• Clear head
• Less sedating

Question 33

Methadone over buprenorphine

Answer 33

• Easier to supervise
• For high levels of heroin
• Sedation is required
• Other opioids prescribed

Question 34

What is suboxone?

Answer 34

Sublingual tab of naloxone w/ buprenorphine

Question 35

What is a missed dose + what happens when it occurs?

Answer 35

• Missed 3 days (lost tolerance)

- Restart initiation