Opioid analgesic therapy

Question 1

Describe the starting regimen of morphine

Answer 1

Start with immediate release morphine
(Adult) 10mg/4hr
(Elderly) 5mg/4 hr
(Very elderly/frail) 2.5mg/hr

Question 2

Describe how dose of morphine is increased

Answer 2

Increase dose in increments of 25-50 percent
No maximum does of opioids
Once pain is well-managed, convert to modified release morphines over 12 hrs for convenience

Question 3

Give examples of immediate and modified release morphines

Answer 3

(Immediate release) Oramorph/Sevredol mixture

(Modified release) MST; Zomorph

Question 4

Describe the conversation of 4 hourly morphine dose to 12 hourly

Answer 4

Divide daily morphine dose based on 4 hourly dose by half to make the 12 hourly dose (e.g. 10mg/4hr becomes 30mg/12hr)

Question 5

State the most appropriate type of morphine for syringe drivers and why?

Answer 5

Diamorphine

More water-soluable than morphine

Question 6

Describe the conversation of oral morphine to SC diamorphine

Answer 6

Divide 24 hour morphine dose by 3

The resulting diamorphine dose is over 24 hours

Question 7

Describe how breakthrough doses are calculated

Answer 7

Use 50-100% of equivalent 4 hourly dose currently being used
(i.e. 270mg/12 hr = 540mg/24 hr is the equivalent of 90 mg/4 hr at 100% and 45mg/4hr at 50%)

Question 8

Give examples of classes of strong opioids

Answer 8

Morphine and similar drugs
Fentanyl 
Methadone 
Intermediate weak-strong opioid
Buprenorphine

Question 9

Give examples of morphine opioids and the benefits of certain types

Answer 9

Morphine; Diamorphine; Hydromorphine; Oxycodone

Hydromorphine and oxycodone are less renal toxic. used in patients with renal failure

Question 10

Give examples of fentanyl and its benefits over morphine

Answer 10

Fentanyl; Alfentanil; Sufentanil

Causes less sedation, cognitive impairment, constipation

No used orally due to high first pass metabolism. Administered via transdermal patch, lozenge or CSIC

Question 11

Describe the uses of methadone and its pros and cons

Answer 11

Useful for treating neuropathic and other pains states not fully responsive to opioids.

However had long and variable half life. Reserved for neuropathic, ischemic or inflammatory pain

Question 12

Describe the uses of tramadol and its pros and cons of using tramadol

Answer 12

Not classed as a controlled drug so has practical prescribing advantages.