Block V- Pulm Asthma Drugs

Question 1

True or false - most of asthma is due to allergies

Answer 1

false - only 30%

Question 2

What causes exacerbations of asthma?

Answer 2

decrease in expiratory airway, air is trapped or occluded

Question 3

What factors cause immediate bronchospasm?

Answer 3

Histamine, PAF, leukotrienes (C4, D4)

Question 4

What causes late bronchospasm?

Answer 4

mast cells, platelets, macrophages releasing chemotaxins and leuotrien B4, PAF

Question 5

What are the major categories of anti asthmatic drugs?

Answer 5

bronchidilator drugs

anti inflammatory drugs

Question 6

What is the mechanism of action of bronchodilator therapy?

Answer 6

beta-2 AR agonist

• causes decrease in Ca and decreased contractility
• hyper polarization of K
• Medication of choice

Question 7

What are some selective Beta-2 AR agonists?

Answer 7

• Metaproterenol
• Albuterol
• Terbutaline
• Bitolerol

Question 8

Why is inhalation therapy of Beta-2 AR agonists preferred?

Answer 8

• more bronchodilation
• fewer AE
• faster onset of action
• lower doses for effects

Question 9

What are the advantages of a compressor driven nebulizer?

Answer 9

• consistent dose without coordination needed

- but are expensive and non portable and prone to bacterial contamination

Question 10

Which B2 AR agonist can be injected subcutaneously?

Answer 10

Terbutaline

Question 11

What is unique about the metabolism of bitolterol?

Answer 11

-prodrug that is activated by lung esterases to tertbutylnorepinephrine

Question 12

Which drug is the standard of inhaled beta-2 agonists for bronchospasm in asthma?

Answer 12

albuterol

Question 13

Which drug is the only beta-2 agonist that can be used by subcutaneous injection for emergency treatment of status asthmatics?

Answer 13

Terbutaline

Question 14

Which drug has the quickest onset of action of ant beta-2 agonist for asthma when inhaled?

Answer 14

Metaproterenol

Question 15

Which drug has a long duration of action (8hr) when inhaled?

Answer 15

Bitolterol

Question 16

Which drug has the longest duration of action of any Beta2 agonist and should be used only for maintenance treatment?

Answer 16

Salmeterol

Question 17

What are the adverse effects of beta-2 agonists?

Answer 17

• Skeletal muscle tremor
• Anxiety, restlessness, apprehension
• Tachycardia

Question 18

Give an example of a Methylxanthine

Answer 18

• Theophylline (oral)

- Amionphylline (IV)

Question 19

What is the MOA of Theophylline?

Answer 19

• Inhibits cAMP Phosphodiesterase, causing buildup of cAMP and Smooth Muscle Relaxation
• Antagonism of adenosine receptors
• interference with uptake and storage of Ca by SR in striated muscle, results in increase in cytoplasmic concentration of Ca ions (increase contraction of cardiac and skeletal muscle)

Question 20

What affects the mean half-life of theophylline?

Answer 20

cigarette smoking shortens it

Question 21

What is notable about Theophylline’s pharmacokinetics?

Answer 21

narrow therapeutic window

Question 22

What are adverse effects of Theophylline?

Answer 22

• Agitation
• Hyperreflexia
• Fasiculations
• Convulsions
• Tachycardia
• Arrhythmias
• Circulatory collapse
• elevated body temp
• Urinary retention

Question 23

What is the MOA of Ipratropium bromide?

Answer 23

Muscarininc receptor antagonist

• anticholinergic drug
• aerosol

Question 24

What is the biochemical effect of Ipratropium bromide?

Answer 24

• inhibits ACh released from airway vagal nerves
• muscarinic receptor antagonist
• RESULTS IN
• decreased concentration of inositol triphosphate
• decreased release of Ca from ER = relaxation of bronchial smooth muscle

Question 25

What are the clinical uses of Ipratropium bromide?

Answer 25

- combo with beta-2 agonists in severe acute asthma or if primary therapies are not well tolerated - with coexisting chronic bronchitis or cough - DOC for chornic bronchitis and emphysema

Question 26

What are adverse effects of Ipratropium bromide?

Answer 26

-drying in the mouth post inhale

Question 27

How are adrenal corticosteroids used for asthma?

Answer 27

- treats the chronic inflammation - decreased inflammation will increase airway diameter - reduced frequency and severity of chronic asthma attacks

Question 28

What are examples of corticosteroids used in asthma?

Answer 28

- Beclomethasone (Inhale) - Flunisolide (Inhale) - Triamcinolone (Inhale) - Predinsone (oral) - Methylpredinsone (IV)

Question 29

What is the biochemical effect of corticosteroids?

Answer 29

- increased lipomodulin - inhibits phospholibpase A2 - supresses arachidonic acid - inhibits release of leukotrienes and prostaglandins - reduces leukocyte chemotaxis and smooth muscle contraction and airway mucus secretion

Question 30

What are the therapeutic uses of adrenal corticosteroids in asthma?

Answer 30

-first line prophylactic therapy for all cases of asthma

Question 31

What are adverse effects of corticosteroids?

Answer 31

Systemic - hyperglycemia - edema - rounding of facial contour - osteoporosis - cataracts - myopathy - HPA axis supression - psychological depression Local - oropharyngeal candidiasis - Dysphonia - dryness of mouth and throat - coughing

Question 32

What is an example of combination therapy ?

Answer 32

Symbicort - mixture of glucocorticoid and long acting B-AR agonist - Butenoside and Formototerol Fumarate

Question 33

What is the clinical indication for Cromolyn sodium?

Answer 33

prevention of asthma attacks - used prior to a challenge such as exercise or cold air - wil not reverse asthmatic bronchospasm - Combination therapy for those who do not respond well to primary lines of treatment

Question 34

What is the mechanism of action of Cromolyn sodium?

Answer 34

- inhibits degranulation of mast cells (prevents release of histamine and other mediators) - reduces transmembrane influx of Ca induced by IgE-antigen interaction - Inhibits recruitment of neutrophils and eosinophils (inhibits NCF) - Attenuates ability of PAF to cause airway hyperractivity

Question 35

What are adverse effects of Cromolyn sodium?

Answer 35

-hypersensitivity (rash)

Question 36

What is the mechanism of action of Zileuton?

Answer 36

Inhibits synthesis of leukotreines by blocking 5-lipoxygenase inhibits actions of LTB4

Question 37

What is the mechanism of action of Zariflukast?

Answer 37

LT receptor antagonist | -blocks LTD4 action

Question 38

What is the mechanism of action of Montelukast?

Answer 38

LT receptor antagonist | -blocks LTD4 action

Question 39

What are the clinical indications of Zariflukast?

Answer 39

- prevent asthmatic attacks in patients over age of 12 - not a rescue medication - reduces the need for rescue medications - improves pulmonary function in mild to moderat asthma - effective in aspirin induced asthma - prevents cold air induced bronchoconstriction

Question 40

What are contraindications of Zariflukast?

Answer 40

breast feeding

Question 41

What are drug interactions of Zariflukast?

Answer 41

any CYP450 metabolized drug - warfarin - inhibits CYP450

Question 42

what are the clinical uses of Zileuton?

Answer 42

- prevent exercise, cold air, and aspirin induced asthma | - reduces nocturnal symptoms

Question 43

What are the adverse effects of Zileuton?

Answer 43

- inc. alanine transaminase - contraindicated with hepatic disease - Dyspepsia

Question 44

What is the mechanism of action of omalizumab?

Answer 44

- monoclonal antibody | - forms a complex with circulating IgE to lower serum concentration levels and prevent IgE from biding to mast cells