Resp Flashcards
What are some examples of Beta2 agonist for resp system?
salbutamol, salmeterol, formoterol, terbutaline
-ol
MOA for Beta2 agonist
Beta2 receptors are found in the smooth muscle of the bronchi, GI tract, uterus and blood vessels
stimulation = smooth muscle relaxation
also stimulate Na+/K+ -ATPase pumps on cell surface membrane - shift of K+ from extracellular to intracellular compartment - hyperkalaemia
what are the different types of Beta2-agonist
short acting (salbutanol, salmeterol) long acting (formoterol, terbutaline)
indication for beta2-agonist
Asthma - short and long acting (step 3 of chronic asthma but must always be given with inhaled corticosteroids)
COPD - short for acute relieve of symptoms, long acting 2nd line treatment of COPD
hyperkalaemia
contraindication of beta2-agonist?
long acting should be be used with inhaled corticosteroid as without will inc asthma death
cardiovascular disease - may provoke angina or arrhythmias
side effect of beta2 agonist
activation of beta2 receptors in other receptors - fight or flight effects - angina, tachycardia, palpitations, anxiety and tremor
promote glycogenolysis - inc serum glucose
high dose - inc serum lactate
long acting - muscle cramps
interaction of beta2 agonist
Beta blocker reduce the effectiveness of beta2-agonist
combination use with theophylline and corticosteroid - hypokalaemia
what is another name for antimuscarinics
anticholinergic
what are some examples for anticholinergics/antimuscarinics
ipratropium, tiotropium, glycopyrronium
MOA for anticholinergics/antimuscarinics
bind to muscarinic receptors (competitive inhibitors of acetylcholine)
activation of the muscarinic receptors bring about parasympathetic effects
blocking this muscarinic receptors have effect of reducing smooth muscle tone, inc heart rate and conduction
also reduce secretions from glands in the resp ad GI tract, relaxation of the pupils in the eye (preventing accommodation)
indication for antimuscarinics
COPD - shorting - relieve breathlessness, long acting - prevent breathlessness and exacerbations
Asthma - short acting - acute relieve, long acting - step 4 of management of asthma with corticosteroids and beta2 agonist
contraindication for antimuscarinics
angle-closure glaucoma - inc intraocular pressure
caution in pt with risk of arrhythmia (activation of the sympathetic system)
side effect of antimuscarinics
if taken by inhalation - little systemic absorption
if oral - dry mouth
interaction of antimuscarinics
N/A
what are some examples of corticosteroids
prednisolone, hydrocortisone, dexamethasone
MOA for corticosteroids for resp system?
exert mainly glucocorticoid effects and mostly prescribe for modification of the immune system response
1 they up-regulate anti-inflammatory genes and down-regulate the pro-inflammatory genes (TNF etc)
2 direct suppression on monocytes and eosinophils
3 metabolic effects incl - inc gluconeogenesis from inc circulating amino and fatty acids released by catabolism of muscle and fat
4 have mineralocorticoid effect - stimulate Na+ and water retention and K+ excretion
indication for corticosteroids for resp system
1 treat allergic or inflammatory disorder eg analphalxis, asthma
2 suppression of autoimmune disease - IBD, inflammatory arthritis
3 treatment for some cancer as part of chemo to reduce tumour-asoociated swelling
4 hormone replacement in adrenal insufficiency or hypopituitarism
contra-indication for corticosteroids
caution with ppl with infection and in children (down-regulated immune response)
side effect of corticosteroids
immunosuppression - inc risk and severity of infection and alters the host’s response
metabolic effects incl DM and osteoporosis
inc catabolism = muscle weakness, skin thinning with easy bruising and gastritis
mood and behavioural changes - insomnia, confusion, psychosis and suicidal risk
mineralocorticosteroid = HTN, hypokalaemia and oedema
adrenal atrophy (if prolonged) - suppress ACTH production - if corticosteroid is wthdraw suddenly, an Addison’s crisis with cardiovascular collapse might occur
chronic glucocorticoid deficiency occur during treatment withdrawal incl fatigue, weight loss, arthralgia
interaction of corticosteroid
inc peptic ulcers and GI bleeding when use with NSAIDs
enhance hypokalaemia in pt taking beta2 agonist, theophylline, loop, thiazide diuretics
effect reduced by cytochrome P450 inducers
where is corticosteroid eliminated
liver and kidney
where is beta2 agonist eliminated
kidney
where is antimuscarinic eliminated
kidney
what is an example of mucolytic?
carbocysteine
