Anti-Asthmatics Study Guide

A series of flashcards covering the key concepts related to anti-asthmatic medications and their mechanisms of action.

Asthma

A chronic inflammatory disorder of the airway characterized by breathlessness, chest tightening, wheezing, dyspnea, and cough.

Chronic Obstructive Pulmonary Disease (COPD)

A chronic, progressive, largely irreversible disorder characterized by airflow restrictions and inflammation.

Glucocorticoids

The principal anti-inflammatory drugs used for asthma treatment, considered the most effective antiasthma drugs available.

Leukotriene Modifiers

Drugs that block leukotriene actions, reducing bronchoconstriction and inflammatory responses in asthma.

Cromolyn

A mast cell stabilizer used as an inhaled medication to prevent the release of histamine and other mediators.

Omalizumab [Xolair]

A monoclonal antibody that antagonizes immunoglobulin E (IgE) to help control asthma.

Interleukin-5 Antagonists

Drugs that inhibit actions of interleukin-5 (IL-5), which activates eosinophils involved in allergic reactions and asthma.

Beta2-adrenergic Agonists

Principal bronchodilators that activate beta2 receptors to promote bronchodilation and relieve bronchospasm.

Phosphodiesterase Inhibitor

A drug that inhibits phosphodiesterase enzymes, increasing levels of cyclic AMP in immune cells, enhancing anti-inflammatory effects.

Methylxanthines

A class of drugs like Theophylline that produce bronchodilation by relaxing smooth muscle and blocking adenosine receptors.

cause of COPD

smoking cigarettes

emphysema

enlargement in the air space of bronchioles and alveoli brought on by the deterioration of the walls of these air spaces

symptoms of COPD

1. chronic cough

2. excessive sputum production

signs and symptoms of asthma

• Sense of breathlessness

• Tightening of the chest

• Wheezing

• Dyspnea

• Cough

cause of asthma

combo of inflammation and bronchoconstriction

symptoms of COPD result from

chronic bronchitis and emphysema

chronic bronchitis results from

hypertrophy of mucus-secreting
glands in the epithelium of the larger airways

anti-inflammatory agents

• Foundation of asthma therapy

• Taken daily for long-term control

mechanism of action of glucocorticoids

• Suppress Inflammation

• Decrease synthesis and release of inflammatory
  mediators

• Reduce infiltration and activity of inflammatory cells

• Decrease edema

inhaled use glucocorticoids

• First-line therapy for management of inflammatory
  component of asthma

• Most patients with persistent asthma should use these
  drugs daily

• Inhaled glucocorticoids are very effective and much
  safer than systemic glucocorticoids

side effects of glucocorticoids

• Can slow growth in children and adolescents;
  however, these drugs do not decrease adult height

• Promotion of bone loss

• Increased risk of cataracts

• Increased risk of glaucoma

• Adrenal suppression

• Prolonged glucocorticoid use can decrease the ability
  of the adrenal cortex to produce glucocorticoids of its
  own

leukotrienes

• Promote smooth muscle constriction
• Promote blood vessel permeability
• Promote inflammatory responses through direct action and recruitment of eosinophils and other inflammatory cells

leukotriene modifiers

block:

• smooth muscle constriction

• blood vessel permeability

• inflammatory responses through direct action and recruitment of eosinophils and other inflammatory cells

Montelukast [Singulair]

Used for prophylaxis, not for quick relief

Mast Cell Stabilizers

• stabilize cytoplasmic membrane of mast cells, thereby
  preventing release of histamine and other mediators

• In addition, they inhibit eosinophils, macrophages, and other inflammatory
  cells

• Considered the safest of all anti-asthma medications

Cromolyn

Route of administration: Inhalation
o Nebulizer

Monoclonal Antibody

Mechanism: Antagonism of immunoglobulin E (IgE), a type of
antibody
- This may initially seems confusing. The “drug” is a class of antibody that binds to and thereby blocks the action of another class of antibody (ile,, IgE)

ex: Omalizumab [Xolair]

Interleukin-5

• cytokine involved in the activation and
  maturation of eosinophils

• expressed by T-lymphocytes and Natural Killer cells

Interleukin-5 Antagonists

inhibit:

• cytokine involved in the activation and
  maturation of eosinophils

• expressed by T-lymphocytes and Natural Killer cells

• ex: reslizumab

Interleukin-5 Receptor Antagonists

These are antibodies that block Il-5 receptors
Examples:
• Benralizumab
• Mepolizamab

Interleukin-4 Receptor Antagonists

antibodies that block one chain of the IL-4 receptor
• Through blockade of this chain, they modulate the signaling of both IL-4 and IL-13
Example: Dupilumab (Dupixent)

Phosphodiesterase Inhibitor

Inhibiting PDE4 leads to increased levels of cAMP in immune cells,
thus increasing anti-inflammatory action
Example: Roflumilast (Daliresp)

Bronchodilators

Provide symptomatic relief but do not alter the underlying disease process
(inflammation)
• In almost all cases, patients taking a bronchodilator should also be taking a
glucocorticoid for long-term suppression of inflammation
• Principal bronchodilators are the beta 2-adrenergic agonists

Beta 2-adrenergic agonists Mechanism

activation of beta 2 receptors in the smooth muscle of the lung, these drugs promote bronchodilation, relieving bronchospasm

Beta 2-adrenergic agonists Use in asthma and COPD

Inhaled short-acting beta 2 agonists (SABAs)
o Taken PRN to abort an ongoing attack

Inhaled long-acting beta 2 agonists (LABAs)

Long-term control in patients who experience frequent attacks

Benefits of inhalation drug therapy:

Therapeutic effects are enhanced
• Systemic effects are minimized
• Relief of acute attacks is rapid

Methylxanthines Mechanism

Produces bronchodilation by relaxing smooth muscle of the
bronchi
o Phosphodiesterase inhibitor
o Blocks adenosine receptors

ex: theophylline

Methylxanthines Use in asthma and COPD:

Oral theophylline is used for maintenance therapy of chronic stable asthma
o Theophylline is no longer recommended for treatment of COPD
Narrow therapeutic index

Anticholinergic Drugs

Improves lung function by blocking muscarinic receptors in the bronchi,
thereby reducing bronchoconstriction

ex: Ipratropium

Aclidinium

Newest long-acting anticholinergic for management of bronchospasm
associated with COPD
• Relieves bronchospasm by blocking muscarinic receptors in the lung

LABA = Long-Acting Beta-Agonists

• Indicated for long-term maintenance in adults and restricted use in
  children

• Not recommended for initial therapy

Available combinations of Glucocorticoid/LABA Combinations

o Budesonide/formoterol [Symbicort]
o Fluticasone/vilanterol [Breo Ellipta]
o Fluticasone/salmeterol [Advair]
o Mometasone/formoterol [Dulera]

Acute Severe Exacerbation goals

Relieve airway obstruction and hypoxemia, and normalize lung
function as quickly as possible

Acute Severe Exacerbation Initial therapy

o Oxygen—To relieve hypoxemia
o A systemic glucocorticoid—To reduce airway inflammation
o A nebulized, high-dose SABA—To relieve airflow obstruction
o Nebulized ipratropium—To further reduce airflow obstruction