Respiratory Drugs Flashcards
Which classes of drugs cause low potassium?
Corticosteroids, beta 2 agonists, methylxanthines (aminophylline)
Which drugs cause tachycardia?
Beta 2 agonist, methylxanthines (theophylline)- come from caffeine
Which classes cause hyperglycaemia in a diabetic patient?
Corticosteroids, beta 2 agonists
Which drugs cause psychiatric side effects?
Corticosteroids, leukotriene receptor antagonist
Which class causes osteoporosis?
Corticosteroids
How do selective beta2 agonists work?
Stimulate b2 adrenoreceptors and cause adenyl cyclase to convert ATP to cAMP which activate a protein kinase
This inhibits myosin light chain kinase inhibits smooth muscle contraction resulting in bronchial smooth muscle relaxation
What is different in dosing of inhaled and nebuliser?
Inhaled 100mcg, nebuliser 2.5mg
How does aminophylline work?
Inhibits phosphodiesterase which breaks down CAMP into AMP, therefore more protein kinase A
What are side effects of SABA?
Fine tremor, resting sinus tachycardia, hypokalaemia
SABA onset and duration?
5 minutes, last 4-6 hours
Onset of action of LABA?
15-45 mins, Formoterol
How do antimuscarinics work?
Bind to muscarinic receptors in bronchial smooth muscle (mainly M2/M3), cause bronchodilator
Tiotropium - selective to m3 due to slow dissociation
What should not be prescribed concurrently?
LAMA inhaler, and SAMA-
SAMA onset and duration?
Onset 30 mins, 3-5 hours
Dose of SAMA?
Nebuliser 500mcg QDS, inhaler 20mcg QDS
When using a nebuliser ipratropium what should you be cautious of?
Narrow angle glaucoma due to increased risk of intraocular pressure
Side effects of antimuscarinics?
Dry mouth, dry eyes, headache constipation