Week 10 drugs only Flashcards
Exam 4
Characteristic signs and symptoms of asthma:
Breathlessness
Tightness in the chest
Wheezing
Dysnea
Cough
Underlying cause of asthma:
The underlying cause is immune-mediated airway inflammation.
Chronic obstructive pulmonary disease (COPD)
is a chronic, progressive, largely irreversible disorder characterized by airflow restrictions and inflammation.
Symptoms of COPD
Symptoms include chronic cough,
excessive sputum production,
wheezing,
dyspnea, and
poor exercise tolerance
How does the inflammatory process of asthma begin?
The inflammatory process begins with binding of allergen molecules (e.g., house dust mite feces) to immunoglobulin E (IgE) antibodies on mast cells.
When allergen molecules bind to IgE antibodies on mast cells in asthma, what happens?
This causes mast cells to release an assortment of mediators, including histamine, leukotrienes, prostaglandins, and interleukins.
What are the two effects that mediators released by mast cells have during asthma?
These mediators have two effects.
- They act immediately to cause bronchoconstriction.
- In addition, they promote infiltration and activation of inflammatory cells (eosinophils, leukocytes, macrophages).
What do the inflammatory cells do during asthma?
These inflammatory cells then release mediators of their own.
What is the end result of airway inflammation?
The end result is airway inflammation characterized by edema, mucus plugging, and smooth muscle hypertrophy, all of which obstruct airflow.
In addition to edema, mucus plugging and smooth muscle hypertrophy, what does inflammation produce?
Inflammation produces a state of bronchial hyperreactivity.
Symptoms of COPD result largely from a combination of two pathologic processes:
- chronic bronchitis
- emphysema.
Chronic bronchitis is defined by:
chronic cough and excessive sputum production
What does chronic bronchitis result from:
results from hypertrophy of mucus-secreting glands in the epithelium of the larger airways
Emphysema is defined by:
Emphysema is defined as enlargement of the air space within the bronchioles and alveoli brought on by deterioration of the walls of these air spaces.
In a smal percentage of people, emphysema results from:
In a small percentage of the population, emphysema results from a genetic alteration that results in alpha-1 antitrypsin deficiency.
Alpha-1 antitrypsin
Alpha-1 antitrypsin is a protease inhibitor that protects the lungs from enzymatic destruction by proteases.)
Two main pharmacological classes of drugs for asthma and COPD:
- Anti inflammatory drugs
- Bronchodilators
Principle antiinflammatory drugs are:
Glucocorticoids
The principal bronchodilators are:
beta2 agonists
For chronic asthma and stable COPD how are glucocorticoids administered? (route and timing)
For chronic asthma and stable COPD, glucocorticoids are administered on a fixed schedule, almost always by inhalation.
For chronic asthma and stable COPD, how are Beta agonists administered?
Beta2 agonists may be administered on a fixed schedule (for long-term control) or as needed (PRN; to manage an acute attack). Like the glucocorticoids, beta2 agonists are usually inhaled.
Most antiasthma drugs can be administered by inhalation: What are the three advantages of this route?
(1) Therapeutic effects are enhanced by delivering drugs directly to their site of action, (2) systemic effects are minimized, and
(3) relief of acute attacks is rapid.
MDI
are small, handheld, pressurized devices that deliver a measured dose of drug with each actuation.
When more than one inhalation is needed for MDIs, how should you take the medication?
When two inhalations are needed, an interval of at least 1minute should separate the first inhalation from the second.
Dry Powder Inhalers (DPIs)
Dry-powder inhalers (DPIs) are used to deliver drugs in the form of a dry micronized powder directly to the lungs.
How do MDIs compare with DPIs?
- DPIs deliver more drug to the lungs
- DPIs are breath activated.
- Spacers are not used with DPIs
Nebulizer
A nebulizer is a small machine used to convert a drug solution into a mist.
What are the most effective drugs available for long term control of airway inflammation?
Glucocorticoids (e.g., budesonide, fluticasone)
How are glucocorticoids usually administered?
Administration is usually by inhalation but may also be IV or oral.
When do systemic glucocorticoids cause adverse effects?
When systemic glucocorticoids are used long term, severe adverse effects are likely.
In general, what do glucocorticoids do?
Glucocorticoids reduce respiratory symptoms by suppressing inflammation.
Specific antiinflammatory effects include of glucocorticoids include?
- Decreased synthesis and release of inflammatory mediators (e.g., leukotrienes, histamine, prostaglandins)
- Decreased infiltration and activity of inflammatory cells (e.g., eosinophils, leukocytes)
- Decreased edema of the airway mucosa (secondary to a decrease in vascular permeability)
By reducing inflammation, what do glucocorticoids do?
- reduce bronchial hyperreactivity and
- decrease airway mucus production.
Therapeutic use of glucocorticoids:
they are especially effective for:
1. asthma prophylaxis and
- for management of COPD exacerbations
What are the first line therapy for management of the inflammatory component of asthma?
Inhaled glucocorticoids
*most patients with persistent asthma should take these drugs daily
Who are oral glucocorticoids required for?
May be required for patients with moderate to severe persistent asthma or for management of acute exacerbations of asthma or COPD.
What is a serious problem with oral glucocorticoids? So when should these drugs be taken? How long should these meds be taken?
They have a potential for toxicity.
These drugs are prescribed only when symptoms cannot be controlled with safer medications (inhaled glucocorticoids, inhaled beta2 agonists)
Because the risk for toxicity increases with duration of use, treatment should be as brief as possible.
Adverse Effects of Inhaled Glucocorticoid:
- Adrenal suppression
- Oropharyngeal candidiasis
- Dynsphonia
- Slow growth of children and adolescents (but don’t decrease adult height)
- Increased risk for glaucoma and cataracts
- May promote bone loss
Potential adverse effects of prolonged oral glucocorticoids include:
adrenal suppression,
osteoporosis,
hyperglycemia,
immunosuppression,
fluid retention,
hypokalemia,
peptic ulcer disease, and,
in young patients, growth suppression.
Prolonged glucocorticoid use and adrenal suppression:
prolonged glucocorticoid use can decrease the ability of the adrenal cortex to produce glucocorticoids of its own.
WHy is adrenal suppression life threatening
This can be life-threatening at times of severe physiologic stress (e.g., surgery, trauma, or systemic infection).
High levels of glucocorticoids are required to survive severe stress and because adrenal suppression prevents production of endogenous glucocorticoids,
At times of stress, what must patients with adrenal suppression be given?
Because high levels of glucocorticoids are required to survive severe stress and because adrenal suppression prevents production of endogenous glucocorticoids, **patients must be given increased doses of oral or IV glucocorticoids at times of stress.
When is adrenal suppression also a concern?
Adrenal suppression is also a concern when
- discontinuing prolonged use of oral glucocorticoids or
- when transferring from an oral route to an inhaled route.
It take months for full adrenal functioning, during that time, what must patients do?
it is important to decrease the dosage gradually. Throughout this time, all patients, including those switched to inhaled glucocorticoids, must be given supplemental oral or IV glucocorticoids at times of severe stress.
How are inhaled glucocorticoids administered?
Inhaled glucocorticoids are administered on a regular schedule—not PRN.
Leukotriene receptor antagonists (LTRAs)
Leukotriene receptor antagonists (LTRAs) suppress the effects of leukotrienes
Leukotrienes
Compounds that promote smooth muscle constriction, blood vessel permeability, and inflammatory responses through direct action and through recruitment of eosinophils and other inflammatory cells.
In patients with asthma, how do (LTRAs) work?
In patients with asthma, these drugs can decrease bronchoconstriction and inflammatory responses such as edema and mucus secretion.
Three LTRAs available and how are they taken?
- Zileutin
- Zafirlukast
- Montelukast
**taken orally
How do current guidelines recommend taking leukotriene receptor antagonists?
- second-line therapy if an inhaled glucocorticoid cannot be used and
- as add-on therapy when an inhaled glucocorticoid alone is inadequate.
Zileuton- what does it do and what is it approved for?
What is does: Blocks leukotriene synthesis
Approved for: Asthma prophylaxis and maintenance therapy in adults and kids