Anti Asthmatic Drugs

Question 1

Asthma symptoms

Answer 1

• Wheezing
• Dyspnoea
• Cough
• Chest tightness

Question 2

Asthma Pathophysiology

Answer 2

• Airway inflammation
• Increased mucus secretion
• Constriction of bronchial smooth muscles

Question 3

Drug categories

Answer 3

• Bronchodilators
• Anti-inflammatory drugs
• Monoclonal antibody

Question 4

Bronchodilators types

Answer 4

• β₂ agonists
• Methyl xanthines
• Anticholinergics
• Leukotriene antagonists

Question 5

Anti-inflammatory agents types

Answer 5

• Mast cell stabilisers
• Inhalational
• Systemic

Question 6

Monoclonal antibody type

Answer 6

Anti-IgE antibody

Question 7

β₂ agonists examples

Answer 7

SABA: salbutamol, terbutaline
LABA: salmeterol, formeterol

Question 8

Methyl xanthines examples

Answer 8

• Theophylline

* Aminophylline

Question 9

Anticholinergics examples

Answer 9

• Ipratropium bromide

* Tiotropium bromide

Question 10

Leukotriene antagonists examples

Answer 10

• Montelukast
• Zafirlukast
• Sodium Cromoglicate
• Nedocromil

Question 11

Mast cell stabilisers examples

Answer 11

• Sodium Cromoglicate

* Nedocromil

Question 12

Inhalational anti-inflammatory agents examples

Answer 12

• Beclomethasone
• Budesonide
• Fluticasone

Question 13

Systemic anti-inflammatory agents examples

Answer 13

• Hydrocortisone

* Prednisolone

Question 14

Anti-IgE antibody example

Answer 14

Omalizumab

Question 15

Salbutamol indication

Answer 15

• Used to terminate attacks
• Not suitable for prophylaxis
• Less cardiac side effects

Question 16

Salmeterol, formeterol indication

Answer 16

• Used for maintenance therapy and nocturnal asthma

Question 17

β₂ agonists side effects

Answer 17

• Headache, palpitations, tremors
• Repeated doses: cardiac arrythmia, death
• Metabolic: hypokalaemia, increased insulin secretion

Question 18

Methyl xanthines MOA

Answer 18

• Decrease cAMP degradation by inhibiting phosphodiesterase

* Slow and sustained bronchial smooth muscle relaxation

Question 19

Theophylline indication

Answer 19

Act as “controller agent” during asthma therapy

Question 20

Theophylline adverse effects

Answer 20

• Overdose: hypertension, arrythmia, convulsion
• CNS: tremor, nausea, insomnia, anxiety
• CVS: palpitation, arrythmia, precordial pain

Question 21

Theophylline drug interaction

Answer 21

• Increased plasma level with enzyme inhibitors (erythromycin)
• Decreased plasma level with enzyme inducers (rifampicin)

Question 22

Ipratropium bromide MOA

Answer 22

• Blocks AcH muscarinic receptors and inhibits bronchoconstriction (M3)

Question 23

Ipratropium bromide indication

Answer 23

• Used prophylactically
• Used with β₂ agonists in acute attack
• Main use in COPD

Question 24

Leukotriene antagonists MOA

Answer 24

• Antagonise LT1 receptor mediated bronchoconstriction
• Bronchodilation, reduced sputum eosinophil count, suppression of bronchial inflammation and hyper reactivity
• Effective in aspirin induced asthma

Question 25

Leukotriene antagonists indication

Answer 25

Used for prophylactic therapy in mild to moderate asthma

Question 26

Mast cell stabilisers MOA

Answer 26

• Inhibits degranulation of mast cells and hence release of histamine, interleukins, PAF, LTs

Question 27

Mast cell stabilisers indication

Answer 27

* For long term prophylactic use * Ineffective if given during an attack * Reduces the number of attacks

Question 28

Corticosteroids MOA

Answer 28

• Reduces bronchial hyper reactivity and mucosal edema

Question 29

Inhaled corticosteroids advantage

Answer 29

Produce very few side effects

Question 30

Inhaled steroid therapy indication

Answer 30

* controller drug * No role in acute Attack * Commonly used with β₂ agonists in mild to moderate asthma

Question 31

Systemic steroid therapy indication

Answer 31

* Severe chronic asthma | * In status asthmaticus not responding to bronchodilator therapy

Question 32

Inhalational steroid therapy adverse effects

Answer 32

* Oropharyngeal candidiasis * Hoarseness of voice * Cough

Question 33

Systemic steroid therapy adverse effects

Answer 33

* HPA axis suppression * Bone resorption * Cataracts * Glaucoma * Steroid myopathy * Skin thinning, purpura * Psychiatric changes

Question 34

Omalizumab MOA

Answer 34

* Inhibits binding of IgE to high affinity receptors (receptors on mast cells, basophils, macrophages etc) * Thus reducing inflammatory response

Question 35

Omalizumab indication

Answer 35

* To reduce steroid dependence * To decrease asthma attacks * For concomitant asthma and allergic rhinitis, nasal allergy, food allergy

Question 36

Management of asthma in adults

Answer 36

• Step 1: mild intermittent asthma: inhaled SABA as required • Step 2: regular preventer therapy: add inhaled steroid • Step 3: initial add-on therapy: LABA Maximise inhaled steroid Consider leukotriene antagonist or SR theophylline • Step 4: persistent poor control: increase steroid Add 4th drug: leukotriene receptor antagonist, SR theophylline or β agonist • Step 5: continuous use of oral steroids: daily steroid tablet

Question 37

Management of status asthmaticus

Answer 37

* Hydrocortisone hemisuccinate * Theophylline slow IV * Salbutamol + Ipratropium bromide - nebulisation with O2 * High flow humidified O2 * Intubation if needed * Correction of electrolyte imbalance and maintain hydration