Respiratory Drugs

Question 1

Classification of Asthma based on Severity

Severity;Symptom Frequency; Nighttime awakening

Answer 1

Intermittent; < 2 per week; < 2 per month

Mild Persistent; > 2 but not daily; 3-4 times per month

Moderate Persistent; Daily; > 1 time a week but not daily

Severe Persistent; Throughout the day; 4-7 times/week

Question 2

Drugs used to manage Asthma

Answer 2

Bronchodilators: acute management

• b2 agonist
• anticholinergics
• methylxanthines

Anti-Inflammatory Drugs: Long term therapy

• corticosteroids
• Release inhibitors
• immunomodulators
• Leukotriene-modifying agents

Question 3

b2 adrenergic agonist Drugs

Answer 3

Inhaled SABA’s

• Albuterol
• Terbutaline
• Pirbuterol

Inhaled LABA’s

• Salmeterol
• Formoterol

Question 4

Inhaled b2 agonist MOA

Answer 4

1) Binds b2 receptors in airway smooth muscle cells
2) activates Adenylyl cyclase
3) increase cAMP production
4) cAMP activates PKA and phosphorylation of MLCK occurs (inactivation)
5) Results in bronchodilation

Question 5

Inhaled SABA’s Uses

Answer 5

DOC for relief of acute asthma symptoms and prevention of exercised-induced bronchospasm1

Question 6

Inhaled LABA’s Uses:

Answer 6

LABA’s combined with inhaled corticosteroids (ICS) for long term control in moderate and sever persistent asthma

Should not be used as mono therapy (no anti-inflammatory actions)

LABA’s are not used in the treatment of acute symptoms or exacerbations

Question 7

b2 agonist AE

Answer 7

Administration via inhalation minimizes AE.

AE: Tachycardia, tremor, and Hypokalemia

LABA’s increase risk of serious asthma related events (hospitalization, intubation, and death)

Question 8

Anticholinergics Drugs

Answer 8

Inhaled SAMA’s
- Ipratropium

Inhaled LAMA’s
- Tiotropium

Question 9

Anticholinergics MOA

Answer 9

Block Muscarinic (M3) receptors on the airways causing bronchodilation and reduction of respiratory secretions

Question 10

Anticholinergic Uses

Answer 10

Ipratropium less effective than SABA’s

Ipratropium paired with SABA’s (addictive effect) to manage moderate-severe exacerbations of asthma

Ipratropium: DOC for b-blocker induced bronchospasm
Tiotropium may be added to ICS for long-term control of severe persistent asthma

Question 11

Anticholinergic AE

Answer 11

Quaternary Ammoniums: (not very lipophilic)

Low access to systemic circulation (low systemic AE)

Minor anticholinergic effects
- xerostomia

May be safer than SABA’s in patients with CVD

Question 12

Mehylxanthines Drugs

Answer 12

Theophylline

Question 13

Theophylline MOA

Answer 13

inhibits PDE

Inc. cAMP evokes Bronchodilation

Question 14

Theophylline Uses:

Answer 14

can be given orally or IV

Alternative therapy for patients with persistent asthma

Question 15

Theophylline AE

Answer 15

Replaced by b2 agonist b/c Narrow Therapeutic Window, AE, and potential for drug interactions

Most Common AE:
headache, N/V, abdominal discomfort, and restlessness

** at high concentrations: cardiac arrhythmias and seizures

Question 16

ICS and Systemic Corticosteroid drugs

Answer 16

ICS:

• Beclomethasone
• Budesonide
• Flunisolide
• Fluticasone

Systemic Corticosteroids

• prednisolone
• dexamethasone

Question 17

Corticosteroids MOA

Answer 17

Inhibits phospholipase A2 and the transcription of COX-2
- results in decrease in leukotrienes and prostaglandins

Note: prolong use of SABA’s results in b2 receptor desensitization
- steroids prevents this or reverses the desensitization

Question 18

Corticosteroid Uses

Answer 18

ICS are the most effective long-term control medication in the management of persistent asthma

oral prednisolone may be added to ICS for long term control of severe persistent asthma

A short course of systemic corticosteroids is used for moderate and severe acute exacerbations of asthma to speed recovery and to prevent recurrence of exacerbations.