1) Salbutamol stimulates airway b1-adrenoceptors.
Incorrect
CORRECT!
It stimulates Beta 2 receptors
2) Ipratropium bromide is antagonist of M3 muscarinic cholinoreceptors on smooth muscle.
CORRECT!
Incorrect
3) Erythromycin may reduce the clearance of theophylline via cytochrome P450 inhibition.
CORRECT!
Need to consider this when prescribing the patients usual dose of theophyllin during an exacerbation.
Incorrect
4) Inhaled corticosteroids have a low therapeutic ratio.
Incorrect
CORRECT!
They have a high therapeutic ratio, meaning that there is a significant difference between the dose needed to achieve therapeutic benefit and the dose that would be toxic.
5) High doses of nebulised inhaled salbutamol may cause hypokalaemia by stimulating Na/K ATP’ase on skeletal muscle cells.
CORRECT!
Incorrect
Question2:
I thought Ipratropium is non-selective muscarinic acetylcholine antagonist?
(and tiotropium is the M3 antagonist)
the question just asks if ipratropium is an antagonist of M3 muscarinic cholinoreceptors on smooth muscle not whether it works exclusively on them.