Drug control in asthma Flashcards

1
Q

What is asthma?

A

Recurrent reversible obstruction of airflow in airways in response to non-noxious stimuli
Difficulty in breathing; wheezing; cough

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are reasons in having asthma?

A
Genetically susceptibility 
Trigger also required
Allergic in >30% 
Post-viral (after infection)
Psychogenic (e.g. stress can be an asthma trigger)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How many people are being treated for asthma in Scotland?

A

390,00

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How many deaths a day are caused by asthma in the UK?

A

5 deaths/day (2000/yr)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is extrinsic asthma?

A

Atopic, allergic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is intrinsic asthma?

A

Non-atopic, non-allergic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are triggers of asthma?

A
Pollen 
Dust
Animal hair
Sting
Aspirin
Cold air
Irritant chemicals
Pollutants
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the immune system?

A

Guards against bacteria, viruses, cancer and parasites. Normally a protective mechanisms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is an antigen?

A

Protein or modified protein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How is antibody synthesis induced?

A

By monocytes (blood) macrophages, lymphocytes, mast cells- IgE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the equation for the immune reaction?

A

A/g + A/b –> immune reaction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What does cell-fixed a/b provide?

A

Recognition
Anchor
Trigger

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What chemical mediators (cytokines) are released by the cell?

A
Interleukins
Prostaglandins (PG) --> recruit other cells to the site of infection
Leukotrienes (LT)
Thromboxanes (Tx)
Histamine
Platelet activating factor )PAF)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the effects of cytokine mediators?

A

Vasodilation
Pain/itch
Oedema- fluid leaks out of tissue, causes congestion
Smooth muscle contraction- contraction of bronchioles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is an allergy?

A

An inappropriate immune response

Form of reaction, mediators involved, vary in different tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are some effects of an allergic reaction?

A

Skin- rash, itch
Gut- vomitting
Eyes, nose- hypersecretion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are the stages of asthma?

A

Intermediate

Late

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the intermediate stage of asthma?

A

Bronchoconstriction (airways constrict), may or may not be vasodilation
Anaphylaxis leads to death

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are the late stages of asthma?

A

Oedema–> congestion
Hyper secretion –> mucus
Inflammatory cells
Bronchoconstriction and hyperreactivity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What does is mean if there is an increase in FEV1 in lungs?

A

Treatment is working, lungs are getting better

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is innervation of the lungs?

A

Parasympathetic
Sympathetic
Non-adrenergic non-cholinergic (NANC)
Sensory- irritation–> reflex constriction via parasympathetic

22
Q

What are upper airways constricted by?

A

Ach via M3 receptors

23
Q

What are M3 receptors?

A

Parasympathetic nerves

24
Q

What constricts the lower airways?

A

NANC transmitters

25
Q

What relaxes the lower airways?

A

NANC transmitters (e.g. NO) and circulating adrenaline (beta 2)

26
Q

What is not in the airway muscle?

A

Sympathetic nerve supply

27
Q

What constricts blood vessel smooth muscle?

A

NA from sympathetic nerves (alpha 1)

28
Q

What relaxes blood vessel smooth muscle?

A

Circulating adrenaline (beta 2)

29
Q

What system does mucus secretion decrease?

A

Sympathetic system

30
Q

What system does mucus secretion increase?

A

Parasymathetic system, inflammatory mediators and chemical/physical stimuli

31
Q

What is the immediate phase of drug therapy?

A

Smooth muscle relaxants (treat bronchospasm)

32
Q

What is the late phase of drug therapy?

A

Steroids (treat inflammation)

33
Q

What drugs are used to treat asthma?

A
Beta-adrenoreceptors agonists
Muscarinic antagonists
Theophylline
Antihistamines 
LT antagonists
Glucocorticoids (anti-inflammatory steroids)
34
Q

What are beta-adrenoceptor agonists?

A

Adrenaline

Alpha + beta agonist

35
Q

What do B1 adrenoreceptors agonists affect?

A

Heart

36
Q

What do B2 adrenoreceptor agonists affect?

A

Bronchi

37
Q

What is salbutamol?

A

Beta 2 only

Inhaled aerosol or powder

38
Q

What does saltbutamol do?

A

Relaxes bronchioles
Decreases secretion
Increases FEV1

39
Q

What is the mechanism of saltbutamol?

A

Increases adenylate cyclase
Increases cAMP
Decreases Ca2+ entry

40
Q

What are examples of drugs for muscarinic antagonists?

A

Ipratropium

Tiotropium

41
Q

What does Ipratropium do?

A

N+ poor absorber
Blocks bronchoconstriction due to parasympathetic reflex
More useful in bronchitis

42
Q

What does Tiotropium do?

A

Prolonged (24hr) M3 selective muscarinic antagonist

Better than the older ipratropium

43
Q

What is theophylline?

A

Bronchodilator

44
Q

How does theophylline relax smooth muscle?

A

Inhibition of phosphodiesterase
Increases cAMP
Increases cGMP
Increases release of NA and Adr

45
Q

What are some possible serious side effects of theophylline?

A

Arrythmia, convulsions, low TI

46
Q

What benefits are antihistamines?

A

Little benefit in asthma (much more in hayfever etc)

47
Q

What do antagonists of leukotrienes (LTs) do?

A

Drugs to block either the LT receptor or the synthesis of LTs
E.g. montelukast

48
Q

What is an example of a useful glucocorticoid (anti-inflammatory steroids)?

A

Beclomethasone- very important as prohphylactic

49
Q

How do glucocorticoides suppress immune system?

A

Decreases lymphocyte and mass cell number
Decreases reactivity
Decreases mediator synthesis and release
Decreases b.v. permeability

50
Q

What is the glucocorticoid mechanism?

A
Cytoplasmic receptor
Nuclear binding
RNA fro lipocortin (Annexin-1) 
Block PLA2
Block COX-2
51
Q

What are the advantages of inhalation?

A
Rapid response
Targetted at bronchi
Need less drug 
Less side effects
Avoid liver metabolism