Opioids

Question 1

What is tramadol?

Answer 1

Synthetic mu-opioids agonist

enhances noradrenergic and serotonergic inhibition or nociceptive transmission

Question 2

What is an advantage of tramadol?

Answer 2

Analgesic with minimal sedation, resp depression, reduced GI ADRs

Question 3

Discuss the use of tramadol in chronic pain

Answer 3

Limited role

Limited analgesic activity, many ADRs/interactions (esp serotonergic drugs that are beneficial in chronic pain management)

Question 4

What kind of laxatives should be used with opioids?

Answer 4

Stimulant laxative + combined with stool softener (docusate & senna)

Osmotic laxatives (macrogol, sorbitol, lactulose)

Question 5

What laxatives are used in resistant cases/established opioid-induced constipation?

Answer 5

Glycerol suppository

Small volume enema

saline laxative

Question 6

Summarise key facts about Targin

Answer 6

Oxycodone/naloxone = equivalent to oxycodone controlled release

Reduces but does not eliminate opioid induced constipation

Can provoke withdrawal symptoms or diarrhoea in people who are opioid tolerant

Question 7

Name some immediate release opioid

Answer 7

Sevredol (morphine)

Ordine (morphine liquid)

Oxynorm

Endome (oxycodone)

Question 8

Name some slow release opioids

Answer 8

MScontin

OxyContin

Question 9

How is dose of opioid calculated?

Answer 9

Start w/ prn immediate release

Add up 24hr dose and divide by 2 = bd controlled release dose

Find the new dose/strength by dividing 24hr bd dose by 2

Question 10

How is opioid breakthrough pain calculated?

Answer 10

24 hr prn dose/12 to 24hr prn dose/6

Question 11

Summarise some key facts about transdermal patches

Answer 11

Appropriate for stable chronic pain NOT ACUTE

Inflexible dose = rapid sage titration impossible

Delayed onset and prolonged action

DO NOT USE FENTANYL PATCHES IN OPIOID-NAIVE PATIENTS –> Toxicity is high

Question 12

What opioids should be avoided in renal impairment?

Answer 12

Codeine

Dextropropoxyphene

Pethidine

Question 13

What opioids should have lower doses in renal impairment?

Answer 13

Hydromorphone

Morphine

Tramadol

Question 14

What opioids are better in renal impairment?

Answer 14

oxycodone

tapentadol

Fentanyl

Question 15

Explain the acronym used to identify opioid toxicity

Answer 15

CPR-3H

C: coma
P: pinpoint pupils
R: respiratory depression
H: hypotension
H: hypothermia
H: hyporeflexia

Question 16

Summarise opioid associated respiratory depression

Answer 16

Serious ADR of opioid

Judged by degree of sedation –> precedes respiratory depression

Late and unreliable indication

Keep sedation score <2, score of 2 means early resp depression

Question 17

Outline the sedation score

Answer 17

0 - wide awake

1 - easy to rouse

2 - easy to rouse, but cannot stay awake

3 - difficult to rouse

Question 18

What are the opioid substitutes?

Answer 18

Methadone

Buprenorphine

Naltrexone

Question 19

What is methadone?

Answer 19

long-acting mu-opioid receptor

Influences NMDA and serotonin receptors

Question 20

What is buprenorphine?

Answer 20

long-acting opioid (half-life 28hr)

Mu-receptor agonists and kappa receptor antagonist

Used in high dose in opioid substitution programs –> reduce craving, suppress w/drawal

Available combined with naloxone to reduce parenteral abuse

Question 21

What is naltrexone?

Answer 21

Opioid antagonist

reinforce abstinence in treatment opioid and alcohol dependence