pain/MSK Flashcards
NSAIDs
- examples? 3
- mechanism of action?
- ibuprofen
- naproxen
- diclofenac
Inhibits COX-2 (and a bit of COX-1)
- inhibits prostaglandins that cause pain
- breaks down gastric mucosa
- pro-thrombotic
- constrict afferent arteriole of renal glomeruli
Nb selective COX-2 inhibitors (eg etoricoxib) were developed to attempt to reduce adverse effects of NSAIDs
- but have increased risk of cardiovascular events…
NSAIDs
- examples?
- two groups of indications?
- ibuprofen
- naproxen
- diclofenac
1) ‘as needed’ for mild-moderate pain (as an alternative to paracetamol, but paracetamol preferred as fewer side effects)
2) regular treatment for pain related to inflammation (particularly MSK and rheumatological)
NSAIDs
- main groups of side effects? 3
- other adverse effects? 2
- which associated with least side effects?
- way of decreasing risk of side effects?
GI toxicity
- indigestion
- ulcers
- bleeds
Renal impairment
- dt constriction of afferent arterioles
CV thrombotic events
- increased risk
- hypersensitivity reaction (angioedema + bronchospasm)
- fluid retention
- ibuprofen least likely to have side effects
Prescribe a PPI
- elderly
- previous PUD
- long term use
- comorbidities
- on other drugs with GI effects
NSAIDs
- absolute contraindications? 4
- relative contraindications? 4
+ severe renal impairment
+ heart failure
+ liver failure
+ known NSAID hypersensitivity
- prior PUD
- GI bleeding
- cardiovascular disease
- renal impairment
Use safest NSAID for shortest possible time
NSAIDs
- interactions which increase risk of GI ulcers? 2
- interactions which increase risk of GI bleeding? 3
- interactions which increase risk of renal impairment? 2
GI ulcer risk
- aspirin
- corticosteroids
GI bleed risk
- anticoagulants
- SSRIs
- venlafaxine
Renal impairment
- ACEi
- diuretics
Nb also NSAIDs reduce therapeutic effects of antihypertensives + diuretics
NSAIDs
- when to take?
- commonest side effect?
- how long to take for acute pain?
- take with food
- indigestion (stop if get and see doc!!)
- take for max 10 days (see doc if pain continues)
weak opiods:
- examples? 3
- mechanism of action?
- main indication?
- tramadol
- codeine
- dihydrocodeine
metabolised in the liver to produce relatively small amounts of morphine
- opiod receptor agonist
nb tramadol is a synthetic analogue of codeine and slightly stronger and probably work on other neurotransmitter pathways as well
1) for mild-moderate pain, second line when paracetamol is insufficient (second rung of pain ladder)
weak opiods:
- examples? 3
- common side effects? 4
- effects of overdose? 2
- tramadol
- codeine
- dihydrocodeine
- constipation
- nausea
- dizziness
- drowsiness
neurological + respiratory depression in overdose
nb tramadol may cause less constipation + respiratory depression than other opiods
weak opiods:
- examples? 3
- relative contraindications for all? 4
- relative contraindication for tramadol? 1
- absolute contraindication for tramadol? 1
- tramadol
- codeine
- dihydrocodeine
- significant respiratory disease
- renal impairment
- hepatic impairment
- elderly
tramadol lowers seizure threshold
- ideally avoid in epilepsy
+ absolutely contraindicated in uncontrolled epilepsy
weak opiods:
- examples? 3
- interaction for all? 1
- interaction for tramadol? 1
- tramadol
- codeine
- dihydrocodeine
other sedating drugs
- antipsychotics
- benzodiazepines
- tricyclic antidepressants
tramadol: other drugs that lower seizure threshold:
- SSRIs
- tricyclic antidepressants
weak opiods:
- which route should codeine + dihydrocodeine NOT be given via?
- what should be prescribed alongside them for regular administration?
- what side effects to warn patients about?
IV (nb can give IM, normally in theatre)
- can give a severe reaction, similar to anaphylaxis, mediated by histamine but not an allergic reaction
- laxatives (normally a stimulant laxative, such as senna)
drowsy/confused
- avoid driving or operating heavy machinery if feel this!
strong opiods:
- examples? 2
- mechanism of action?
- morphine
- oxycodone
activation of opiod receptors
- reduce neuronal excitability + pain transmission
- in the medulla, blunt response to hypoxia + hypercapnoea, reducing resp drive + breathlessness
- reduce sympathetic response to pain, thus reduce cardiac activity + oxygen demand
nb oxycodone is synthetic analogue of morphine
strong opiods:
- examples? 2
- two indications for pain relief?
- two other indications?
- morphine
- oxycodone
1) rapid relief of acute severe pain (incl post-op pain + acute MI)
2) relief of chronic pain (where paracetamol, NSAIDs + weak opiates are insufficient) - rung 3 of WHO pain ladder
3) relief of breathlessness in end-of-life care
4) relieve breathlessness + anxiety in acute pulm oedema
- alongside oxygen, furosemide + nitrates
strong opiods:
- examples? 2
- common side effects? 7
- symptoms of withdrawal reaction, if dependent? 5
- morphine
- oxycodone
- respiratory depression
- euphoria + detachment (neurological depression in high doses)
- nausea + vomiting
- pupillary constriction (edinger-westphal nucleus)
- constipation
- itching/urticarial/vasodilation + sweating (dt histamine release)
- tolerance + dependence (prolonged use)
opposite effects to clinical use:
- anxiety
- pain
- breathlessness
- dilated pupils
- cool + dry skin with piloerection (‘cold turkey’)
strong opiods:
- examples? 2
- relative contraindications? 5
- oxycodone
- morphine
- hepatic failure
- renal failure
- resp failure (generally only give if palliative)
- elderly
- biliary colic (as may cause spasm of sphincter of odi -> more pain)