Asthma

Question 1

• Directly act upon B2 adrenoceptors on bronchiole smooth muscle to relax it
• Causes dilation
• Inhibits mediator release fro mast cells and monocytes
• May act on cilia to aid mucus clearance
• Tremor
• Tolerance may develop
• May absorb into systemic circulation

Answer 1

B2 Adrenic Receptor Agonists

Question 2

• B2 adrenic receptor agonists
• Short- acting, max effect in 30 mins
• Lasts 4-6 hours
• Used as required

Answer 2

Salbutamol and Terbutaline

Question 3

• B2 adrenic receptor agonists
• Long acting
• Lasts 12 hours
• Given 2x daily

Answer 3

Salmeterol

Question 4

• 2nd line drug used with steroid
• Given IV in acute severe asthma
• Targets B2 on bronchiole smooth muscle
• Causes dilation
• Inhibits mediator release from mast cells and monocytes
• May act on cilia to clear mucus
• Acts as phosphodiesterase inhibitor= muscle relaxation
• Tremor, sleep disturbance, stimulate heart, vasodilation, anorexia, N+V

Answer 4

Xanthine (THEOPHYLLINE)

Question 5

• Used in combination with B2 agonists and steroids
• Max effect of 30 mins, given every 3-5 hours
• Aerosol inhalation
• Blocks action of endogenous acetylcholine at muscarinic receptors
• Bronchodilation, decreases mucus secretion aiding clearance
• Poorly absorbed into systemic circulation= fewer side effects

Answer 5

Ipatropium (MUSCARINIC RECEPTOR ANTAGONIST)

Question 6

• Action additive with B2 agonists
• Used for mild to moderate asthma
• Given orally

Answer 6

Leukotriene receptor antagonists

Question 7

• Leukotriene recpetor antagonists
• Act on the cysteinyl leukotriene receptors on mast cells
• Prevents action of LTC4 and LTD4 which usually cause bronchiole constriction and stimulate mucus production
• Few side effects- may cause headache and GI disturbance

Answer 7

Montelukast and Zirfirlukast

Question 8

Mechanism is not fully understood

Answer 8

Cromoglicate

Question 9

• Cromoglicate
• Reduce bronchial hyper-activity
• Inhibits T-cell cytokines and affects inflammatory cells
• Used in asthma caused by antigens, exercise, irritants
• Most effective in children
• Effects may take weeks to develop
• Irritation of upper respiratory tract and hypersensitivity reactions

Answer 9

Nedocromil Sodium

Question 10

Beclometasone, Budesonide and Fluticosone Propionate are examples of…

Answer 10

Glucocorticoids used in Asthma

Question 11

• Reduce bronchospasm
• Bind to DNA in nucleus and alters gene transcription
• Effective in asthma caused by antigens, exercise, irritants
• Reduces neuronal reflexes
• Inhibits T-cell cytokines
• Oropharyngeal thrush, dysphonia, reduced drug deposition in oropharyngeal and increased deposition in airway, adrenal suppression

Answer 11

Glucocorticoids

Question 12

Xolair is an example of…

Answer 12

Oalizumab (BIOLOGICS)

Question 13

• Recombinant DNA-dervived humanised-> IgGI monoclonal antiboy
• Subcut injection every 2-3 weeks
• Absorbed slowly= peak 7-8 days
• Binds to human IgE, inhibits its binding to IgE receptor, inhibits IgE mediated cascade of asthma
• Anaphylais, malignancies

Answer 13

Oalizumab (BIOLOGICS)