It Ain't easy being Wheezy: Respiratory Drugs 1 Flashcards
Autonomic Nervous System control of airways
In airways, what does the sympathetic system stimulate to release and what does this cause
think adrenal gland, adrenaline, B-2 adrenoceptors and smooth muscle
- stimulates adrenal gland to release adrenaline circulating in the blood
- this activates B-2 adrenoceptors in bronchial smooth muscle
- this causes relaxation of smooth muscle and thus bronchodilation
Autonomic Nervous System control of airways
What do B2-adrenergic receptor agonists mimic the effects of?
they mimic the effects of adrenaline
Autonomic Nervous System control of airways
In airways, what does the parasympathetic system stimulate to release and what does this cause?
think cranial nerves, what receptors are activated and then what this subsequently causes
vagus nerve is stimulated and then releases ACh
- this activates M3-receptors in bronchial smooth muscle
- this causes the contraction of smooth muscle and thus bronchoconstriction
autonomic Nervous system control of airways
What type of drug can you use to nullify the effects of the parasympathetic system in the bronchi
You can use muscarinic ACh receptor antagonists
B2-adrenergic receptors
What are the 1st choice drugs for acute condition and give 2 examples for fast acting version of this drug and 2 examples of a long acting version of this drug
- B2 adrenergic receptor agonists are the 1st choice drugs for acute conditions
fast acting:
- salbutamol
- formoterol
long acting:
- salmeterol
- forrmoterol
B2 adrenergic receptor agonists
what are 3 features of B2 adrenergic receptors agonists
think bronchi, mast cells and inflammatory mediators, and mucus
- Bronchodilation
- stabilise mast cells and inhibit inflammatory mediator release
- create enhanced mucociliary clearance
B2-adrenergic agonists adverse effects
what are 7 adverse effects of B2 adrenergic agonists
think skeletal muscles, heart issues, metabolism, bronchi and oxygen blood concentration
SHTMPH
skeletal muscle tremor
hypokalaemia (potassium deficiency leading to muscle cramps)
tachycardia and arrhythmias
metabolic responses
paradoxial bronchospasm
Hypoxaemia
limitations of B2-adrenergic agonists
what is a limitation of B2-adrenergic agonists
think tolerance
the body can build tolerance/become less sensitized to them.
Muscarinic acetylcholine receptor antagonists
How are muscarinic ACh receptor antagonists given?
inhalation/nebulizer
Muscarinic acetylcholine recepotr anatagonists
what is 1 example of:
- fast acting Muscarinic Ach receptor antagonist
- long acting muscarinic Ach receptor antagonist
fast acting: Ipratropium
long acting: tiotropium
muscarinic acetylcholine recepotr antagonists
where else, other than the vagus nerve may ACh be released?
non-neuronal cells in the airways
muscarinic acetylcholine receptor antagonists
what 2 things other than bronchodilation, can muscarinic ACh receptor antagonists cause and what does it not effect?
think mucus and clearance of mucus for what it effects
think inflammation for does not effect
causes:
- decrease mucus secretion in asthma
- increases mucociliary clearance (bringing up of mucus from the lungs)
Does not effect: inflammatory phase of asthma
muscarinic receptor antagonists: adverse effects
how can you reduce the adverse effects of muscarinic receptor antagonists and why does this reduce the adverse effects??
think about form of administration and what this creates little of
administer the drugs via inhalation as there is little systemic absorption
Methylxanthines - Theophylline
what are third choice drugs for bronchodilation and give one example of one we need to know
third choice drug: Methylxanthines
example: theophylline
Methylxanthines - Theophylline
how do methylxanthines cause relaxation of smooth muscle and thus cause bronchodilation
think enzyme beginning with P and what it does, then think about what is stopped when methxylxanthines act on it
it inhibits phosphodiesterase from breaking down cAMP to AMP and blocks adenosine receptors
