Pharmacology: Asthma Flashcards
Classify asthma and COPD into reversible and irreversible bronchospasm.
Asthma - reversible
COPD - irreversible
Are bronchodilators considered relievers or controllers?
relivers
Are anti-inflammatory considered relievers or controllers?
controllers
1st line treatment for asthma?
B2 agonists
Symptoms of asthma
chest tightness
shortness of breath
coughing and wheezing
Which leukotrienes are of importance in the treatment of asthma?
LTC4, LTD4,
LTB4 (attract inflammatory cells to airways)
Understand and explain picture.
Immunologic model for the pathogenesis of asthma.
Exposure to antigen causes synthesis of IgE, which binds to and sensitizes mast cells and other inflammatory cells.
When such sensitized cells are challenged with antigen, a variety of mediators are released that can account for most of the signs of the early bronchoconstrictor response in asthma.
LTC4, D4, leukotrienes C4 and D4; ECF-A, eosinophil chemotactic factor-A; PGD2, prostaglandin D2.
What are the 5 goals in the management of asthma?
Prevent chronic and troublesome symptoms
Maintain (near) “normal” breathing
Maintain normal activity levels, including exercise
Prevent recurrent asthma flare-ups, and minimize the need for emergency room visits or hospitalizations
Provide optimal medication therapy with no or minimal adverse effects
What are the drugs useful in the treatment of asthma. (in general give classifications not drug names)
Bronchodilators
Anti-inflammatory drugs
Leukotriene antagonists play dual role
Reproduce chart so memory of treatment strategies is easy to understand.
Reproduce chart.
What are the classes of bronchodilators used in the treatment of asthma?
Beta2 agonists, muscarinic antagonists, and theophylline (methylxanthine)
What are the anti-inflammatory agents used in the treatment of asthma (name of class of drugs)?
corticosteroids
Leukotriene antagonists have what reliever or controller effects? What are they typically used for?
The leukotriene antagonists have effects on both bronchoconstriction and inflammation but are used only for prophylaxis.
Reproduce this chart to understand drugs used in asthma.
Reproduce chart.
Bronchodilators can relax airway smooth muscles but cannot treat what other symptoms of asthma?
mucosal edema, cellular infiltration, or mucus formation
What are the SABA?
Albuterol
levalbuterol
turbutaline
metaproteronol
What are the LABA?
Salmeterol, formoterol
Name the sympathomimetics that can be used?
epinephrine, ephedrine A,B agonists
isoproteronol B agonists
What are the methylxanthines that can be used in asthma patients
theophylline
List the muscarinic antagonists that can be used in the treatment of asthma.
ipratropium, tiotropium
List the glucocorticoids that can be used in the treatment of asthma.
all the asones
beclomethasone
fluticasone
mometasone
dexamethasone
budesonide
Name the leukotriene antagonists drugs used in the treatment of asthma.
montelukast, zafirlukast, zileuton
Name the anti-IgE antibody drugs that can be used in the treatment of asthma.
omalizumab
What is mepolizumab?
IL-5 antagonist monoclonal antibodies
Name the drugs that are used to prevent mast cell degranulation
cromolyn sodium
nedocromil sodium
What should drugs to prevent mast cell degranulation be used for
prophylaxis
What are some important combination of inhaled steroids and long-acting bronchodilators that are becoming widespread in use?
fluticasone/salmeterol (Advair)
budexonide/formetorol (Symbicort)
Explain what this chart is trying to say and draw out.
Bronchodilation is promoted by cAMP which can be increased by:
β2-adrenergic agonists that increase its synthesis by adenylyl cyclase
Phosphodiesterase (PDE) inhibitors that slow its degradation
Bronchoconstriction can be inhibited by: muscarinic or adenosine antagonists
What class of B2 adrenergic agonists are used for acute asthmatic attacks?
SABA
How long to long acting LABA’s drugs take to act?
12 hours
Can LABAs used alone increase asthma mortality?
yes
Common adverse effects of B2 adrenergic agonists.
skeletal muscle tremor, tachycardia, hypokalemia, nervousness and occasional weakness
What is the benefit of using levalbuterol?
Inhalant which is claimed to have fewer central nervous system (CNS) and cardiac adverse effects
Which class of bronchodilators are considered purine derivatives?
methylxanthines
MOA of methylxnthines.
It produces bronchodilation by inhibiting the enzyme cyclic nucleotide phosphodiesterase. Increased levels of cAMP results, which explains the cardiac stimulation and smooth muscle relaxation produced by these drugs.
It blocks adenosine receptors. Adenosine acts as a local mediator contracting smooth muscles, so the blockage of receptors produces opposite response.
What is pentoxifylline’s drug class and benefit?
Another methylxanthine derivative, pentoxifylline, is promoted as a remedy for intermittent claudication; this effect is said to result from decreased viscosity of the blood.
What are some adverse effects of using methylxanthines?
cardiac stimulation CNS excitation tremors and insomnia etc Therefore cardiac arrhythmias, and seizures may result from overdosage.
MOA of anticholinergics for treatment of asthma?
agents reverse vagally mediated bronchospasm.
Also decrease mucus gland hyper secretion seen in asthma
Between iprtropium bromide and tiotropium, which drug has a longer duration of action and is used for COPD?
Tiotropium
How can anticholinergics be given in the treatment of asthma?
given by aerosol or nasal spray
When are systemic (oral) corticosteroids used in the treatment of asthma?
systemic (oral) corticosteroids are used chronically only when other therapies are unsuccessful.
What is the common first-line therapy for inidividuals with moderate to severe asthma?
corticosteriods
What are some toxicities of corticosteroids?
oropharyngeal candidiasis or hoarseness from vocal cord irritation .
When used long term > Cushing’s effects
MOA leukotriene modulators.
Leukotriene receptor antagonists. (CysT1 receptors)
Leukotriene syntheses inhibitors
block 5-lipoxygenase activity
What are 2 leukotriene drugs now available as oral tablets?
montelukast and zafirlukast
MOA of Omalizumab
anti-IgE monoclonal antibody
reduces bronchospastic antigen responses (reduction in frequency and severity of asthma exacerbations)
Who is Omalizumab prescribed for?
mainly prescribed for patients with with moderate to severe persistent asthma who have a positive skin test or in vitro reactivity to a perennial aeroallergen and whose symptoms are inadequately controlled with inhaled corticosteroids.
MOA of Mepolizumab?
IL5 antagonist
What is Mepolizumab used for?
indicated for add-on maintenance treatment of patients with severe asthma aged 12 years and older, and with an eosinophilic phenotype
What is the MOA of the mast cell stabilizers? Use?
These drugs are thought to act by inhibiting mast cell degranulation and, as such, have no direct bronchodilator action, but inhibit both antigen- and exercise-induced bronchospasm in asthmatic patients.
MOA of chromones?
Mechanism not clearly known.
Combination of various effects.
Stabilize mast cells thereby preventing mediator release.
Inhibition of irritant receptors, nerves, plasma exudation and inflammatory cells.
Most important use for cromolyn and nedocromil?
astma (especially in children)
ROA of chromes.
nasal or eye drop
Loxamide. ROA and use?
formulated as an ophthalmic solution to treat ocular allergies, including vernal keratitis and vernal conjunctivitis
Treatment of status asthmaticus.
Humidified Oxygen
Terbutaline
Hydrocortisone
Nebulized Albuterol/terbutaline + ipratropium bromide intermittent inhalation.
Antibiotics for chest infections
Correct dehydration and acidosis
Treatment of COPD in acute symptoms.
Acute symptoms: inhalation of a short-acting β agonist (eg, albuterol) with or without anticholinergic drug (eg, ipratropium bromide).
Treatment of COPD in persistent symptoms.
Persistent symptoms (exertional dyspnea and limitation of activities): regular use of an LABA or a long-acting anticholinergic, or the two together, is indicated.
