Prescribing Analgesia Flashcards
What do you need to check before prescribing paracetamol?
1) Weight of patient- patients weighing 50kg or less have a maximum dose of 500mg QDS
2) History of liver impairment
What do you need to check before prescribing an NSAID?
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
What type of analgesia are paracetamol and NSAIDS?
Simple analgesics
Give three examples of weak opioids
Tramadol, codeine and dihydrocodeine
Give five examples of generic strong opioids
Morphine, diamorphine, buprenorphine, oxycodone and fentanyl
Give four examples of analgesics only prescribed by specialists in palliative care
Hydromorphine, Alfentanil, Ketamine and Methadone
What should be considered before prescribing a patient opioids?
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?
How does the potency of codeine and tramadol compare to oral morphine?
Codeine and Tramadol are 1/10th as potent as oral morphine
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?
40mg/24 hours therefore 20mg oral morphine, modified release, BD.
Describe what is meant by background and breakthrough pain
Background pain is pain at rest. Breakthrough pain involves transient exacerbations of pain which can be predictable (movement) or unpredictable.
What is the difference in potency between morphine and oxycodone?
Oxycodone is 2x as potent than morphine (there half the dose is needed)
What is the difference between morphine and oxycodone?
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.
What is the duration of action of an immediate release opiate?
4 hours. Used to treat breakthrough pain.
What is the duration of action of a modified release opiate?
12 hours. Used to treat background pain.
PRN dose are generally …….. of the 24 hour dose?
1/6th
To reduce chance of side effects of opioids, what anticipatory drugs should be prescribed?
Stimulant laxative
Antiemetic
What are some common side effects of opioids? What are some of the less common side effects?
Common- constipation, nausea, sedation, dry mouth
Less common- psychosis, confusion, myoclonus
*= tend to improve after 1 week
What needs to be included on a prescription for a controlled drug?
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
When are fentanyl patches indicated?
-Stable and opioid responsive pain
-When side effects of oral medication are intolerable
-Oral route difficulties e.g. compliance or dysphagia.
Renal impairment
Are fentanyl patches suitable for acute pain?
No- takes 12 hours for the patch to reach analgesic concentrations.
How often do fentanyl patches need to be changed?
Every 72 hours
When would you consider prescribing zolendronic acid?
Bone bone (type of bisphosphonate)
When would you prescribe steroids?
Compression symptoms
When would you prescribe baclofen?
Muscle spasms (antispasmodics)
What is the difference in potency between injectable (syringe driver) and oral opioids?
In a syringe driver, SC doses of opioids are 2x as strong than oral doses.
How should patients requiring opioids with renal impairment be managed?
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)
How can you assess whether the mediation has improved symptoms?
Pain intensity/frequency
Sleeping through night without pain
Improved functioning and mobility
