Bronchodilator and Anti-inflammatory Drugs in the Treatment of Asthma

Question 1

What are the two types of drugs used in Asthma?

Answer 1

Relievers, and controllers/preventors

Question 2

How do Relievers work?

Answer 2

They act as bronchodilators

Question 3

Examples of relievers

Answer 3

Short acting B2-adrenoceptor agonists. Long acting B2-adrenoceptor agonists. CysLT1 receptor antagonists.

Question 4

How do controllers/preventers work?

Answer 4

They act as anti-inflammatory agents that reduce airway inflammation.

Question 5

Examples of controllers/preventors

Answer 5

Glucocorticoids - cromoglicate. Humanised monoclonal IgE antibodies.

Question 6

What is the comparison with aerosol and oral in pharmokenetics?

Answer 6

Aerosol - Slow absobtion from lung surface and rapid systemic clearance
Oral - Good oral absorbtion (with exceptions) and slow systemic clearance.

Question 7

What is the comparison with aerosol and oral in dose.

Answer 7

Aerosol - Low dose delivered rapidly to target.

Oral - High systemic dose necessary to achieve an appropriate concentration in the lung.

Question 8

What is the comparison with aerosol and oral in systemic concentration of drug?

Answer 8

Aerosol - low

Oral - High

Question 9

What is the comparison with aerosol and oral in incidence of adverse effects.

Answer 9

aerosol - Low

Oral - High (but depends on drug)

Question 10

What is the comparison with aerosol and oral on distribution of drug.

Answer 10

aerosol - reduced in severe airways disease

oral - unaffected by airways disease.

Question 11

What is the comparison with aerosol and oral in Compliance

Answer 11

aerosol - Good with bronchodilators, less so with anti-inflammatory drugs.
Oral - good

Question 12

What is the comparison with aerosol and oral in ease of administration

Answer 12

aerosol - difficult for small children and infirm people (old/feeble)
Oral - good

Question 13

What is the comparison with aerosol and oral in effectiveness

Answer 13

Aerosol - good in mild to moderate disease

Oral - good even in severe disease.

Question 14

What do B2-adrenoceptor agonist do?

Answer 14

Act as physiological antagonists of all spasmogens. Prevents the mechanism of airway smooth muscle contraction.

Question 15

What are the three clasifications that B2 - adrenoceptor agonists come under?

Answer 15

Short-acting(SABA) , long-acting(LABA) and ultra long-acting(ultra-LABA)

Question 16

When are SABA used?

Answer 16

First line of treatment for mild or intermittent asthma. They are relievers as they are taken when needed.

Question 17

How are SABA administered and in what situation?

Answer 17

They are usually administered by inhalation via metered dose/dry powder devices (lessens systematic effect.
In children they use oral and IV for emergencies.

Question 18

How rapidly do SABA act?

Answer 18

within 5 minutes when inhaled with the maximal effect within 30 minutes. This will last for 3-5 hours.

Question 19

Apart from relax the bronchial smooth muscle, what else does SABA do?

Answer 19

Increase mucus clearance and decrease mediator release from mast cells and monocytes.

Question 20

Given 2 examples of SABA

Answer 20

Salbutamol, terbutaline

Question 21

Adverse effects of SABA?

Answer 21

Very few due to unwanted systemic absorption when administered by inhalation. A fine tremor can happen.
However, tachycardia, cardiac dysrythmia and hypokalaemia can occur.

Question 22

Give 2 examples of LABA

Answer 22

Salmeterol and formoterol

Question 23

When are LABA useful and not useful.

Answer 23

Useful for nocturnal asthma as they act for aprox 8 hours.

Not recommended for acute relief of bronchospasm (salmeterol is too slow - not formoterol tho)

Question 24

What does LABAs need to be administered with?

Answer 24

glucocorticoid

Question 25

Which is better, non-selective or selective B2-adrenoceptor

Answer 25

The use of selective B2-adrenoceptors can reduce potentially harmful stimulation of cardiac B1-adrenoceptors. Non-selective B-adrenoceptors antagonists in asthmatic patient is contraindicated (risk of bronchospasm)

Question 26

What does a cysteinyl leukotriene (CysLTs) receptor antagonists do?

Answer 26

They act as a competitive inhibitor for the cysLT1 receptor.

Question 27

What are the 3 cysLTs are derived from mast cells and inflammatory cells and what do they do?

Answer 27

LTC4, LTD4 and LTE4. They cause smooth muscle contraction, mucus secretion and oedema.

Question 28

How are CysLT1 receptor antagonists effective?

Answer 28

They are effective as a add on therapy against early and late bronchospasms in mild persistent asthma. They are usually with other medication (corticosteriods in severe conditions)

Question 29

What types of asthma are CysLT1 receptor agonist effective against?

Answer 29

Antigen-induced and exercise-induced bronchospasms

Question 30

How are CysLT1 receptor agonist administrated?

Answer 30

Orally

Question 31

What are cysLT1 receptor agonist not recommended for?

Answer 31

Relief of acute severe asthma

Question 32

What are the symptoms of cysLT1 receptor agonists?

Answer 32

They are generally well tolerated, although headache and gastrointestinal setup have been reported.

Question 33

Give two examples of cysLT1 receptor agonists

Answer 33

Montelukast and Zafirlukast

Question 34

Name a commonly used group of Xanthines

Answer 34

Methylxanthines

Question 35

Give two examples of methylxanthines

Answer 35

Theophylline and aminophylline

Question 36

What is methylxanthine in?

Answer 36

Coffee, tea and chocolate-containing beverages.

Question 37

What is the possibility of what methylxanthines do?

Answer 37

They inhibit PDE which inhibits the potentiating the action of cAMP in Airway smooth muscle in the B2-adrenoceptor pathway.