Strong opioids

Question 1

Morphine

Answer 1

Choice oral opioid for severe pain in palliative care.
- Also used for coughs in palliative care.

Question 2

What SE does morphine cause the most?

Answer 2

Euphoria
N + V

Question 3

Dose

Answer 3

IR = every 4 hours
MR = 12 or 24 hourly
Maximum dose increments = 1/3 or 1/2 of total daily dose per 24 hr

Question 4

Conversions

Answer 4

Oral –> SC, IV, IM
Half the oral dose

Question 5

Alternative to morphine

Answer 5

Oxycodone
- More potent
- Similar efficacy/SE profile
- 2 times stronger, therefore give half the morphine dose.

Question 6

Parenteral route

Answer 6

Diamorphine (heroin)
Preferred over morphine when administering parenterally.
- More soluble
- Smaller volume can be injected in emaciated patients in palliative care

Question 7

Morphine to diamorphine - conversion

Answer 7

1/3rd of oral morphine dose

Question 8

What is one benefit of diamorphine

Answer 8

Less nausea and hypotension than morphine

Question 9

Transdermal route

Answer 9

Long acting
- Buprenorphine
- Fentanyl

Question 10

Buprenorphine

Answer 10

S/L for opioid dependence
Patches available as:
- 72 hour (3 days)
- 96 hour (4 days)
- 7 days

Question 11

Buprenorphine - activity

Answer 11

Partial agonist (also has antagonistic properties)
May precipitate withdrawal symptoms, for example in those who are opioid-dependent and were previously taking another opioid.

Question 12

Fentanyl

Answer 12

72 hour patch
Risk of fatal repi

Question 12

Buprenorphine - toxicity

Answer 12

Effects are only partially reversed by naloxone in opioid toxicity

Question 13

Fentanyl MHRA

Answer 13

Risk of fatal respiratory depression in opioid naive patients who have not be previously treated wit a strong opioid
Only use if opioid tolerant

Question 14

Fentanyl - counselling

Answer 14

Immediately remove patch and seek prompt medical attention if:
- Breathing difficulties
- Marked drowsiness
- Confusion
- Dizziness
- Impaired speech

Question 15

Fentanyl - switch due to hyperalgesia

Answer 15

Reduce dose of new opioid by 1/4 to 1/2

Question 16

When is the transdermal route unsuitable?

Answer 16

Acute or rapidly changing pain
- Long time to steady state prevents rapid titration of dose.
- Should only be given when dose and pain is stable

Question 17

Patches - application

Answer 17

• Apply to dry, non-irritated and non-hairy skin on upper torso or upper arm.
• Rotate patch site after use
• Avoid exposure toe external heat e.g. hot baths, sauna (increased absorption = more SE and toxicity)