Prescribing Analgesia

Question 1

What do you need to check before prescribing paracetamol?

Answer 1

1) Weight of patient- patients weighing 50kg or less have a maximum dose of 500mg QDS
2) History of liver impairment

Question 2

What do you need to check before prescribing an NSAID?

Answer 2

1) Renal function
2) Platelet count
3) History of asthma- can be triggered
4) History of GI/duodenal bleed
5) Drug history- warfarin, digoxin or steroids

Question 3

What type of analgesia are paracetamol and NSAIDS?

Answer 3

Simple analgesics

Question 4

Give three examples of weak opioids

Answer 4

Tramadol, codeine and dihydrocodeine

Question 5

Give five examples of generic strong opioids

Answer 5

Morphine, diamorphine, buprenorphine, oxycodone and fentanyl

Question 6

Give four examples of analgesics only prescribed by specialists in palliative care

Answer 6

Hydromorphine, Alfentanil, Ketamine and Methadone

Question 7

What should be considered before prescribing a patient opioids?

Answer 7

Age and frailty
Have they taken opioids before? If so, what was their experience?
What is the likely compliance?
Have you prescribed medication for their side effects?
Do they have any co-morbidities?
What is their renal function?
Are they driving?
Do they have any particular concerns?

Question 8

How does the potency of codeine and tramadol compare to oral morphine?

Answer 8

Codeine and Tramadol are 1/10th as potent as oral morphine

Question 9

A pharmacist wants to swap a patient from tramadol to oral morphine. They are currently taking 400mg/24 hours of tramadol. What dose of oral morphine should be prescribed?

Answer 9

40mg/24 hours therefore 20mg oral morphine, modified release, BD.

Question 10

Describe what is meant by background and breakthrough pain

Answer 10

Background pain is pain at rest. Breakthrough pain involves transient exacerbations of pain which can be predictable (movement) or unpredictable.

Question 11

What is the difference in potency between morphine and oxycodone?

Answer 11

Oxycodone is 2x as potent than morphine (there half the dose is needed)

Question 12

What is the difference between morphine and oxycodone?

Answer 12

Both are strong generic opioids. Morphine is a naturally derived opiate whereas oxycodone is synthetic. Oxycodone is 2x as potent than morphine, more expensive and typically associated with fewer side effects. Therefore, it is often only considered if morphine cannot be tolerated.

Question 13

What is the duration of action of an immediate release opiate?

Answer 13

4 hours. Used to treat breakthrough pain.

Question 14

What is the duration of action of a modified release opiate?

Answer 14

12 hours. Used to treat background pain.

Question 15

PRN dose are generally …….. of the 24 hour dose?

Answer 15

1/6th

Question 16

To reduce chance of side effects of opioids, what anticipatory drugs should be prescribed?

Answer 16

Stimulant laxative

Antiemetic

Question 17

What are some common side effects of opioids? What are some of the less common side effects?

Answer 17

Common- constipation, nausea, sedation, dry mouth
Less common- psychosis, confusion, myoclonus
*= tend to improve after 1 week

Question 18

What needs to be included on a prescription for a controlled drug?

Answer 18

1) Name, DOB and address of patient
2) Name of medication - stating whether it is MR or IR
3) Dose - in mg (not ml)
4) Route
5) Frequency (if regular med)
6) Form e.g. liquid/capsule
7) Minimum interval (as required)
8) Maximum to be taken in 24 hours (as required)
9) Additional instructions
10) Name of prescriber
11) Signature of prescriber
12) Bleep number

Question 19

When are fentanyl patches indicated?

Answer 19

-Stable and opioid responsive pain
-When side effects of oral medication are intolerable
-Oral route difficulties e.g. compliance or dysphagia.
Renal impairment

Question 20

Are fentanyl patches suitable for acute pain?

Answer 20

No- takes 12 hours for the patch to reach analgesic concentrations.

Question 21

How often do fentanyl patches need to be changed?

Answer 21

Every 72 hours

Question 22

When would you consider prescribing zolendronic acid?

Answer 22

Bone bone (type of bisphosphonate)

Question 23

When would you prescribe steroids?

Answer 23

Compression symptoms

Question 24

When would you prescribe baclofen?

Answer 24

Muscle spasms (antispasmodics)

Question 25

What is the difference in potency between injectable (syringe driver) and oral opioids?

Answer 25

In a syringe driver, SC doses of opioids are 2x as strong than oral doses.

Question 26

How should patients requiring opioids with renal impairment be managed?

Answer 26

Stay on current opioid but consider reducing dose/frequency. OR switch opioid to a more “renal friendly” option e.g. fentanyl, buprenorphine, methadone, alfentanil (get help from palliative care)

Question 27

How can you assess whether the mediation has improved symptoms?

Answer 27

Pain intensity/frequency
Sleeping through night without pain
Improved functioning and mobility