Respi - asthma

Question 1

causes of asthma

Answer 1

• chronic airway inflammation
• hyperresponsiveness of the airway
• recurrent reversible airway obstruction

Question 2

2 main groups of anti-asthma drugs

Answer 2

1. prevention (controller) - anti-inflammatory drugs

2. provide relief - bronchodilators

Question 3

6 groups of anti-inflammatory (control) anti-asthma drugs

Answer 3

[NIL]

• inhaled corticosteroids (ICS)
• inhaled Na cromoglygate
• leukotriene receptor antagonist (LTRA)
• anti-IgE
• anti-IL-5R
• anti-IL-4R

Question 4

ICS drug

Answer 4

fluticasone - has high receptor binding affinity

-sonide/ -solide

Question 5

ICS MOA

Answer 5

• Decrease secretion of inflammatory cells (T cells, mast cells, macrophages, eosinophils) in airways
• Decrease epithelial cell shedding
• Decrease macrophage phagocytosis and cytokine production and proteases
• Decrease PLA2, COX II, 5-LOX (inflammatory enzymes), increase annexins = downregulate leukotriene expression
• Increase airway SM b-receptors
• reduce plasma exudate/mucus secretion

Question 6

ICS indication

Answer 6

nocturnal asthma
1st line asthma prophylaxis
reduce long term asthma complications like airway remodeling

Question 7

ICS ADR

Answer 7

oropharyngeal candidiasis (candida infection) and irritation
dysphonia (hoarseness of voice)
- fluticasone: adrenal suppression

Question 8

leukotriene modifiers (receptor antagonists) drugs

Answer 8

(-lukast)

• montelukast
• zafirlukast
• zileutone

Question 9

montelukast and zafirlukast MOA

Answer 9

inhibit LTC4/LTD4

• inhibits bronchoconstriction,
• hyper-responsiveness,
• mucosal edema,
• mucus hypersecretion,
• SM hyperplasia

Question 10

montelukast target receptor and indications

Answer 10

competitive antagonist of CysLT1 (cysteinyl leukotriene)
indications:
- prophylaxis + chronic treatment
- aspirin/ exercise induced asthma
(aspirin induced: aspirin inhibits AA -> prostaglandin, so AA -> LTA4 -> LTC4 -> asthma)
ORAL

Question 11

montelukast ADR

Answer 11

psychological: agitation, hallucination, depression

Question 12

Na cromoglycate MOA

Answer 12

inhibit mast cell degranulation (IgE mediated) -> prevent release of inflammatory cells (histamine, prostaglandins, leukotrienes)

Question 13

Na cromoglycate clinical use

Answer 13

paeds asthma

prophylaxis for asthma & allergic rhinitis/ conjuctivitis

Question 14

Na cromoglycate ADR

Answer 14

throat irritation, dryness, cough

Question 15

Omalizumab (anti-IgE mAb) MOA

Answer 15

attacks Fc portion of IgE antibodies

• binds to IgE
• decrease expression of receptors
• decrease mediator release
• decrease inflammatory response and possible exacerbation

Question 16

Omalizumab clinical use + method

Answer 16

allergic asthma, allergic rhinitis

injection every 2-4wks

Question 17

Anti-IL-5R (-zumab) and anti-IL-4R (dupilumab) clinical use + method

Answer 17

severe asthma

subcutaneous injection

Question 18

6 groups of bronchodilators (beta agonists) as asthma RELIEVERS

Answer 18

• non-selective (1-3hrs)
• short acting: SABA (4-6hrs)
• long acting: LABA (12hrs)
• long acting for COPD (24hrs)
• methylxanthine: theophylline
• muscarinic antagonists: SAMA (3-5hrs)/ LAMA (24hrs)

Question 19

non-selective drug

Answer 19

epinephrine

Question 20

SABA drug

Answer 20

salbutamol

Question 21

salbutamol

Answer 21

rapid onset

hydrophilic

Question 22

LABA drugs + clinical use

Answer 22

(-terol)
- salmeterol
- formoterol* - preferred choice (faster onset of action)
long term maintenance of asthma (esp nocturnal asthma)

Question 23

formoterol

Answer 23

rapid onset

amphiphilic

Question 24

salmeterol

Answer 24

slow onset - less useful for emergency use

lipophilic - slowly bind and release

Question 25

LABA drug for COPD

Answer 25

indacaterol

Question 26

beta agonists ADR

Answer 26

``` decrease muscle contraction: tremors, cramps peripheral vasodilation palpitations and tachycardia hypokalemia, hyperglycemia LABA: asthma related mortality ```

Question 27

theophylline MOA

Answer 27

- inhibits PDE + blocks adenosine - increase cAMP -> relaxation - release of epinephrine - anti-inflammatory effects but not as effective as a bronchconstrictor

Question 28

theophylline clinical use + method

Answer 28

add on to inhaled beta agonists + ICS (inhaled corticosteroids) nocturnal bronchospasm COPD: improve lung fn Oral/IV

Question 29

theophylline ADR

Answer 29

narrow therapeutic range - be careful esp DDIs GI: n/v, anorexia CNS: anxiety, tremors CVS: arrhythmia

Question 30

muscarinic antagonists drugs

Answer 30

SAMA: short acting - ipratropium bromide LAMA - tiotropium (-tropium)

Question 31

ipratroprium bromide MOA + method

Answer 31

inhibit m3 receptors = decrease inflammation decrease bronchospasms and mucus secretion less effective as a bronchodilator inhaled, does not cross BBB also used as a mucoregulator

Question 32

ipratropium clinical use

Answer 32

add on to beta agonists + IHC alternative for those intolerant to b agonists COPD - bronchodilator effect

Question 33

tiotropium clinical use

Answer 33

severe asthma | COPD - more potent than SAMA for COPD

Question 34

MA ADR

Answer 34

dry mouth urinary retention in elderly (paradoxical) bronchospasm - supposed to decrease