Asthma Drugs

Question 1

Drugs used in Asthma treatment

Answer 1

Relievers - Act as bronchodilators such as short acting beta2 adrenoceptor agonists (SABA), LABA, CysLt1 receptor antagonists
Controllers - Anti-inflammatory agents that reduce airway inflammation such as Glucocorticoids, cromoglicate and humanised monoclonal IgE antibodies

Question 2

What is aerosol route preferred over oral in Asthma

Answer 2

Aerosol is preferred as it reduces unwanted side effects

Question 3

Mechanism of beta2-adrenoceptor agonists

Answer 3

Beta2-adrenoceptor agonists stimulate via Gs which activates adenylyl cyclase. This converts ATP to cAMP causing uptake of protein kinase A. This causes phosphorylation of myosin light chain kinase and myosin phosphatase resulting in relaxation

Question 4

First line treatment for mild intermittent asthma

Answer 4

Short acting B2-adrenoceptor agonist - Salbutamol, Terbutaline

Question 5

When is oral and IV SABA delievered

Answer 5

Oral in children, IV in emergency

Question 6

How long does action of SABA last

Answer 6

3 to 5 hours

Question 7

Adverse effects of SABA

Answer 7

Fine tremors, tachycardia, arrhythmias, hypokalaemia

Question 8

Can LABA be used as a monotherapy

Answer 8

No, LABA must always be given together with a glucocorticoid. Ex of LABA are Salmeterol and Formoterol.

Question 9

What medication is useful for nocturnal asthma

Answer 9

LABA, 8 hour action

Question 10

What can increase risk of bronchospasms

Answer 10

Use of non-selective beta blockers: Propanolol

Question 11

What does cysteinyl leukotriene do in the body

Answer 11

LTC4, LTD4 and LTE4 from mast cells and infiltrating inflammatory cells cause smooth muscle contraction, mucus secretion and oedema

Question 12

What type of asthma drugs CysLT1 receptor antagonists

Answer 12

Bronchodilators, block CysLT receptors

Question 13

Effective add-on therapy for mild, intermittent asthma

Answer 13

CysLT1 receptor antagonist, Montelukast and Zafirlukast

Question 14

What are CysLT receptor antagonists effective against

Answer 14

Antigen and exercise induced asthma

Question 15

Drugs with bronchodilatory and anti-inflammaroy

Answer 15

Methylxanthines such as Theophylline, Aminophylline

Question 16

Second line drugs for Asthma

Answer 16

Methylxanthines, use wit SABA/LAMA or glucocorticoids

Question 17

Adverse effects of Methylxanthines

Answer 17

In therapeutic window - Nausea, vomiting, abdominal discomfort and headache
Supra-therapeutic - Disarrhythmias, seizures, hypotension

Question 18

Effects of Methylxanthines

Answer 18

Increase diaphragmatic contraction, reduce fatigue, increase mucus clearance, activates histone deacetylase which may potentiate anti-inflammatory action of glucocorticoids, bronchodilation (high dose)

Question 19

Two classes of steroid hormones released by adrenal cortex

Answer 19

Mineralocorticoids (zona glomerulosa) and Glucocorticoids (zona fasciculata)

Question 20

Processes regulated by glucocorticoids

Answer 20

Decrease inflammatory and immunological response

Question 21

What do mineralocorticoids do

Answer 21

Aldosterone - Regulate retention of salt and water in kidney

Question 22

Main prophylaxis treatment of Asthma

Answer 22

Glucocorticoids such as beclometasone, budesonide and fluticasone

Question 23

What receptors do glucocorticoids use for signalling

Answer 23

Glucocorticoids signal via nuclear receptors, GR alpha
Glucocorticoids increase transcription of genes encoding anti-inflammatory proteins and suppress transcription of genes encoding inflammatory ones

Question 24

How do glucocorticoids switch off expression of inflammatory genes

Answer 24

They recruit histone deacetylase (HDAC) to activate genes and switch off gene transcription

Question 25

Effects of glucocorticoids

Answer 25

Prevent production of IgE, reduce number of mast cells, and decrease Fc expression (IgE receptors), decrease formation of Th2 cytokines and cause apoptosis of Th2 and eosinophils

Question 26

Can glucocorticoids relieve allergen or exercise induced asthma

Answer 26

No as it takes time for it's mechanism of action, prevent inflammation to function.

Question 27

Can glucocorticoids be given for mild/intermittent asthma

Answer 27

Yes, efficacy develops over several days

Question 28

Common glucocorticoid adverse effects

Answer 28

``` Dysphonia - Hoarse and weak voice Oropharyngeal candidiasis (thrush) ```

Question 29

Common ICS

Answer 29

Beclometasone, budesonide or flucticasone

Question 30

What is given in chronic, severe or rapidly deteriorating asthma

Answer 30

Oral prednisolone + ICS to reduce oral dose required and reduce unwanted systemic effects

Question 31

Second line prophylactic drugs in allergic asthma

Answer 31

Cromones

Question 32

Second line anti-inflammatory drugs

Answer 32

Cromones eg. Sodium cromoglicate

Question 33

What inhaled drug is more effective in children than adults

Answer 33

Inhaled sodium cromoglicate

Question 34

Recent treatment for asthma associated with severe eosinophilia

Answer 34

Monoclonal antibodies directed against IL-5: Mepolizumab

Question 35

How does Omalizumab (intravenous) work

Answer 35

Monoclonal antibodes againsts IgE. Binds IgE via Fc receptors to prevent attachment to mast cells, reduces Fc receptor expression on inflammatory cells.