resp drugs Flashcards
how do B2-adrenoreceptor agonists work
stimulate sympathetic system:
agonist binding to B2-Gs stimulates adenylyl cyclase —> ATP to cAMP —> PKA —> phosphorylates and stimulates myosin phosphatase, phosphorylates and inhibits MLCK —> relaxation
what is LABA always co-prescribed with and why
glucocorticoid - as a mono therapy LABA would desensitise receptors
what is a LABA particularly good in
nocturnal asthma
what are some side effects of BAs
fine tremor
hypotension
tachycardia
hypokalaemia
how do xanthines work
inhibit phosphodiesterase which increases cAMP (breakdown of cAMP is inhibited) —> PKA + so on
also activate HDAC
true/false
xanthines increase diaphragmatic contractility and reduce fatigue - improve lung ventilation
true
what drug is used as prophylaxis of allergic asthma/rhinitis particularly in children
sodium chromoglicate (inhaled)
what is the mechanism of action of cromlins
mast cell stabiliser - suppresses histamine release from mast cells
what are some side effects of xanthines
numerous drug interactions narrow therapeutic index seizures dysrhythmia nausea vomiting hypotension abdo discomfort headache
how do cysteinyl leukotriene receptors work
act competitively at CysLT1 receptors
prevents binding of CysLTs (C4, D4, E4) released from mast cells which cause SM contraction, mucus secretion and oedema
when are CysLTs Antagonists used
antigen or exercise induced asthma
asthma step 4 - reliever
rhinitis
what are some side effects of CysLTs
abdominal pain
headaches
what are some side effects of corticosteroids
oropharyngeal candidiasis dysphonia growth restrictions glaucoma diabetes cushings
how do glucocorticoids enter the nucleus and what do they do
nuclear receptor GR-alpha
bind to promotor region and either promote or repress transcription of a gene
decreases formation of IL4, 5, 7, 13
what is the mechanism of action of omalzimuab (IV)
binds IgE via Fc to prevent attachment to FC receptors on mast cells - prevents activation
and reduced expression of Fc receptors on inflammatory cells
monoclonal Ab against IgE
what is a side effect of a cromlin
local irritation
what is a side effect of omalzimuab
abdominal pain
pyrexia
when is omalzimuab used
allergic asthma
what are cetirizine, loratadine and fexofenadine
antihistamines - competitive H1 receptor antagonists - reduce effect of mast cell activation
what are H1RAs used to treat
allergic rhinitis
what are some side effects of H1RAs
drowsiness
palpitations
hypotension
what is oxymetazoline and what is it used for
selective alpha-1 agonist - mimics affects of NA - vasoconstriction
rhinitis
what is a side effect of oxymetazoline
medicamentosa - nasal congestion caused by desensitisation of receptor
what is rofumilast
PDE4 antagonist
