Pain/MSK Flashcards
naproxen
NSAID
how does naproxen/NSAIDs work?
inhibits sybthesis of prostaglandins which cause pain and inflammation
= reduces pain and inflammation
indications for NSAIDs/naproxen
mild to moderate pain alongside paracetamol
MSK inflammatory pain - rheumatoid arthritis, severe osteoarthritis, gout
contraindications of NSAIDs/naproxen
severe renal impairment, heart failure, liver failure
NSAID hypersensitivty
peptic ulcer disease, GI bleeding, CVD renal impairment = low dose
side effects of NSAIDs/naproxen
idigestion
GI toxicity
renal impairment
risk of CV events
interactions of NSAIDs/naproxen
increase risk of adverse effects -
GI ulceration: aspirin, corticosteorids
GI bleeding: anticoagulants, SSRIs, venlafaxine
renal impairment: ace in. diuretics
increased risk of bleeding with warfarin and reduces therapeutic effects of antihypertensives and diuretics
morphine
opiod
how do opioids work?
reduce neuronal excitability and pain transmission
reduce response to hypoxia and hypercapnia = reduce respirayroy drive and breathlessness
reduce anxiety
= reduce sympathetic nervous system
indications for morphine
rapid relief of acute severe
+ pain associated with acute MI
chronic pain when paracetamol, NSAIDs and weak opioids are insufficient
relief of breathlessness for end of life
relieve breathlessness and anxiety in acute pulmonary oedema alongside oxygen, furosemide and nitrates
contraindications of morphine
reduce doses in hepatic and renal failure/impairment and in elderly
do not give in respiratory failure except in palliative
aoid in biliary colic as can cuases spasm of sphincter of oddi which can worsen pain
side effects of morphine
respiratory depression euphoria and detatachment depression nausea and vomiting pupillary constriction constipation itchy skin, vasodilation, sweating tolerance and dependence
possible interactions of morphine
not used with other sedating drugs
if not possible, close monitoring is necessary
codeine
opioid
indications for codeine
mild to moderate pain
diarrhoea
dry or painful cough
contraindications of codeine
acute respiratory depression comatose patients head injury (affect pupils in neurological assessment) raised intracranial pressure acute UC
side effects of codeine
arrhythmias confsion constipation dizziness drowsiness dry mouth euphoric mood flushing hallucination headache etc
dependence and addiction
paracetamol
first line analgesic
antipyretic
how does paracetamol work?
inhibits COX-2
= reduces fever and increases pain threshold
indications for paracetamol
first line analgesic for most forms of acute and chronic pain
reduce fever
contraindications of paracetamol
risk of liver toxicity - increased NAPQI produced or chronic excessive alcohol use
reduced glutathione stores
side effects of paracetamol
very few
overdose = liver failure
cure for paracetamol overdose
glutathione precursor acetylcysteine
interactions of paracetamol
cytochrome P450 inducers - phenytoin, carbamazepine, increase rate of NAPQI production and risk of liver toxicity
allopurinol
Xanthine oxidase inhibitors
how do xanthine oxidase inhibitors/allopurinol work?
lowers uric acid concentrations and reduces precipitation of uric acid in joint or kidney
indications for allopurinol
prevent acute attacks of gout
prevent uric acid and calcium oxalate renal stones
prevent hyperuricaemia and tumour lysis syndrome associated with chemotherapy
contra-indications of allopurinol
should not be started in an acute attack of gout, but can be continued if already on it
recurrent skin rash or severe hypersensitivity to allopurinol
reduced dose in renal and hepatic impairment
side effects of allopurinol
skin rash, can be more serious - stevens johnsns syndrome or toxic epidermal necrolysis
can trigger or worsen an acute attack of gout
interactions of allopurinol
allopurinol inhibitsd metabolism of mercaptopurine and increases risk of toxicity
+ amoxicillin increases risk of skin rash
+ACEi or thiazides, increases risk of hypersensitivity reactions
