respi - drugs for asthma

Question 1

1st line bronchodilator in asthma

Answer 1

β2-adrenoceptor agonist

Question 2

1st line anti-inflam in asthma

Answer 2

corticosteroid

Question 3

name a SABA

Answer 3

salbutamol

Question 4

name a fast-acting LABA

Answer 4

formoterol

Question 5

name a slow-acting LABA

Answer 5

salmeterol

Question 6

name an ultra-long-acting β2 agonist

Answer 6

indacterol

Question 7

moa of β2 agonist

Answer 7

1. bronchodilation
2. mast cell stabilisation
3. ↑ mucociliary clearance
4. ↓ microvascular leakiness

Question 8

adverse effect of β2 agonist

Answer 8

1. downreg of β2 receptors → reduced efficacy of β2-agonist-induced bronchodilation when required to relieve acute asthma attack
2. tremors and muscle cramps
3. palpitations and tachycardia
4. hypokalaemia/hyperglycaemia

Question 9

moa of ipratropium bromide

Answer 9

• SAMA
• inhibit M3 receptor-mediated bronchoconstriction
• reverses vagal nerve-mediated bronchospasm and mucus secretion
• adjunct to β2 agonist

Question 10

adverse effects of ipratropium bromide

Answer 10

1. dry mouth
2. urinary retention
3. unpleasant taste

Question 11

moa of theophylline

Answer 11

• inhibits phosphodiesterases (PDEs)
• blocks adenosine receptors
• ↑ adrenaline release from adrenal medulla
• stimulate CNS respi centres
• some anti-inflam effects (stabilise mast cells, ↓ microvascular leakiness)

Question 12

adverse effects of theophylline

Answer 12

• narrow therapeutic window
• many DDIs
• GI: nausea, vomiting, abdominal discomfort, anorexia
• CNS: nervousness, tremors, anxiety, insomnia, seizures
• CVS: arrhythmias

Question 13

eg of ICS used in asthma

Answer 13

budesonide, fluticasone

Question 14

factors that determine which ICS is selected for

Answer 14

1. high receptor binding affinity –> low dose req (less systemic effects)
2. extensive 1st pass metab (less systemic effects)
3. highly lipophilic –> can be taken up well into lungs

Question 15

moa of ICS

Answer 15

• ↑ β2 adrenoceptors
• ↓ airway hyperresponsiveness →↓ freq of acute asthma exacerbations
• prevent airway wall remodelling
• prevent late rxn (nocturnal asthma)

Question 16

adverse effects of ICS

Answer 16

1. oropharyngeal candidiasis
2. dysphonia (due to muscle wasting)
3. cough/throat irritation
4. adrenal suppression
5. easy bruising
6. posterior subcapsular cataracts
7. osteoporosis

Question 17

name 2 leukotriene pathway inhibitors and their targets

Answer 17

1. motelukast (CysLT receptor antagonist)
2. zileuton (5-LOX inhibitor)

Question 18

advantage of montelukast over zileuton

Answer 18

montelukast is a weak bronchodilator (on top of anti-inflam effects)

Question 19

uses of leukotriene pathway inhibitors

Answer 19

1. prophylaxis and chronic treatment of asthma
2. NSAID exacerbated asthma
3. exercise-induced asthma

Question 20

adverse effects of leukotriene pathway inhibitors

Answer 20

1. Churg-Straus syndrome
2. glucocorticoid withdrawal
3. suicidal thinking and neuropsychiatric adverse effects

Question 21

moa of cromoglicic acid

Answer 21

• mast cell stabiliser →↓ mast cell degranulation
• ↓ secretion of inflam mediators
• ↑ secretion of annexin A1→ inhibit prostaglandin and leukotriene prodn
• prevents antigen, cold, dry air and exercise-induced bronchospasm

Question 22

adverse effect of cromoglicic acid

Answer 22

1. throat and nasal irritation, dry mouth, cough
2. unpleasant/bitter taste → affect compliance

Question 23

moa of omalizumab

Answer 23

• anti-IgE Ab
• depletes free IgE in serum
• decreases FcεRI expression on mast cells

Question 24

adverse effects of omalizumab

Answer 24

• small increase in risk of heart attack, TIA and blood clots
• potential for anaphylaxis

Question 25

name 2 anti-IL5 signalling Ab

Answer 25

1. reslizumab (IV)
2. mepolizumab (SC)