Drugs used to treat asthma

Question 1

Beta2-adrenoreceptor agonists MOA

Answer 1

Bind to beta 2 adrenoreceptors to cause relaxation

Question 2

b2-Adrenoceptor Agonists desired effects

Answer 2

Fast acting and effective relievers

Reverse bronchoconstriction due to range of excitatory mediators
– histamine, leukotrienes etc.
Inhibit mediator release from mast cells

Stimulate cilia beat frequency
– increase clearance of mucus

Question 3

b2-Adrenoceptor Agonists adverse effects

Answer 3

can mask inflammatory activity
– bronchodilation without reversal of inflammation

Question 4

short-acting b2-Adrenoceptor Agonists

Answer 4

salbutamol

Question 5

extended acting b2-Adrenoceptor Agonist

Answer 5

formoterol

Question 6

Glucocorticoids

Answer 6

• Frontline therapy for asthma
• Used prophylactically
  – prevent, reduce, reverse airway inflammation
• Anti-inflammatory actions for the long-term treatment of asthma
• Used in combination with b2 agonists
• Administered via inhalation and orally

Question 7

Glucocorticoids MOA

Answer 7

Stimulate lipocortin synthesis
– inhibits phospholipase A 2 activity
– prevents release of arachidonic acid
– decrease synthesis of leukotrienes and prostaglandins and thromboxaines

Inhibit cyclooxygenase activity
– decrease prostaglandin synthesis

Question 7

Glucocorticoids desired effects

Answer 7

1. decrease influx of inflammatory cells
2. decrease mediator release from eosinophils
3. increase number of b 2-adrenoceptors
4. decrease microvascular permeability

Question 8

Glucocorticoids ADEs

Answer 8

Inhaled preparations
– oropharyngeal candidiasis (thrush)
– use of spacer device reduces incidence of thrush

Oral preparations
– suppression of hypothalamic-pituitary-adrenal axis
* adrenal insufficiency
* decrease capacity to synthesise corticosteroids
– osteoporosis
* bone maintenance involves endogenous steroids

Question 9

Leukotriene receptor antagonists MOA

Answer 9

Bind to leukotriene receptor preventing leukotriene binding
- decreases LTB4 eosinophil recruiting
- decrease LTC4,D4,E4 bronchoconstriction

Preventing bronchoconstriction and inflammation

Question 10

Leukotriene receptor antagonists administration

Answer 10

• administered orally
• useful in the elderly and young patients
  eliminates: difficulty with spacer use, reduces glucocorticoid use in children

Question 11

Leukotriene receptor antagonists desired effects

Answer 11

– block leukotriene-induced bronchoconstriction
– block eosinophil trafficking (LTB4)
– reduce glucocorticoid dose in adults

Question 12

Muscarinic antagonists MOA

Answer 12

– block acetylcholine-induced bronchoconstriction
– block acetylcholine-induced secretion of mucus
– no anti-inflammatory actions
- administered via inhalation

Question 13

Antibody to IgE MOA

Answer 13

• Antibody binds to immunoglobulin E (IgE)
• decreases the amount of circulating IgE
• decreases the magnitude of allergic response when exposed
• administered via subcutaneous injection

Question 14

Antibody to IgE desired effects

Answer 14

decrease allergic response

Question 15

Antibody to IgE patients

Answer 15

• adults and adolescents (6 years and
  older) with moderate to severe persistent asthma
• perennial aeroallergen
  – inadequate control with inhaled/oral glucocorticoids
  – decrease glucocorticoid required to control asthma
  – decrease the incidence of asthma exacerbations
  – decrease hospitalisations

Question 16

Antibody to Interleukin-5 MOA

Answer 16

Bind to interleukin-5 preventing it from binding to receptor:
– reduces eosinophil recruitment and survival
– reduces eosinophil numbers and mediator release

Administered by intravenous injection

Question 17

Antibody to Interleukin-5 desired effects

Answer 17

reduces the frequency and severity of asthma exacerbations