Asthma drugs Flashcards
General principles of Asthma management
The overall objectives of antiasthma therapy are to:
To return lung function to as near normal as possible
To prevent acute exacerbations of the disease
To achieve a normal quality of life
Permits normal activities (exercise)
Primary classes of drug therapy
Bronchodilators
Anti-inflammatory agents
Referred as RELIEVERS
- they provide rapid symptomatic relief
Bronchodilators
Referred as CONTROLLERS
-provide long-term stabilization of symptoms
Anti-inflammatory agents
Used both in maintenance therapy and as needed to reverse acute attacks
Bronchodilators
Must be used in conjunction with bronchodilators except for mild asthma
Anti-inflammatory agents
All treatment regimens should include PATIENT EDUCATION that is focused on the following:
- The appropriate use of medications to control symptoms
- Recognition of the signs of a deteriorating disease status
- Prevention strategies
A/E of Epinephrine
Feeling of nervousness and anxiety
Hand and upper extremity tremors
Palpitation
Extreme hypertension, CVA, pulmonary edema, angina and arryhythmias
A/E of Isoproterenol
Tachycardia, dizziness and nervousness
A/E of B2 adrenoreceptors
Muscle tremor
Tachycardia and palpitations
Pharmacological effects of Theophylline
Smooth muscle relaxation
CNS excitation
Cardiac stimulation
Theophylline inhibits
cyclic nucleotide phosphodiesterases
Actions of Theophylline in Asthma
Antagonism of adenosine Inhibition of mediator release Increased sympathetic activity Alteration in immune cell function Reduction in respiratory muscle fatigue
Effect of theophylline is px with Heart failure, liver disease and severe respiratory obstruction
Slow down its metabolism
A/e of theophylline
Nausea and vomiting (most frequent for those receiving for the first time) (20mcg/ml)
Probability of seizures (>40 mcg/mL)
Arrhythmia, hypotension, and cardiac arrest (bolus IV injection)
Effect of theophylline in children
In children: restlessness, agitation, diuresis, fever.
T/F: Theophylline Half life is prolonged in patients with CHF
TRue
T/F: You can give theophylline with Cimetidine and Zileuton
False: Extreme caution in patients who are medicated with Cimetidine & Zileuton
Adrenomimetic agents are use both as ____ & ____ to maintain patency over the long term
These agents are used both as needed to reverse acute episodes of bronchospasm and prophylactically to maintain airway patency over the long term.
Pharmacologic effects of adrenomimetic agents
Pharmacologic effects: bronchodilation, tachycardia, anxiety and tremor.
What are examples of the bronchodilator drugs
Epinephrine Isoproterenol Selective Beta 2-adrenoceptor agonist Theophylline Anticholinergics
Action of epinephrine
activates both alpha and beta receptors
Epinephrine is administered
Subcutaneously
Administered subcutaneously to manage severe acute episodes of bronchospasm and status asthmaticus
Epinephrine timing of effect
5-15 minutes
Measurable improvement in pulmonary function is maintained for up to four hours
Epinephrine cardiovascular effcts
increased heart rate, increased cardiac output, increased stroke volume, elevation of systolic pressure, decrease in diastolic pressure and decrease in systemic vascular resistance.
Isoproterenol action
Beta adrenoceptor agonist
Not selective for b1 and B2
Isoproterenol administration
inhalation
Administered exclusively by inhalation from metered dose inhaler or from nebulizers
Isoproterenol is mainly used for
bronchospasm
Isoproterenol timing effect
Effect is instantaneous but short-lived
Examples of Selective Beta 2-adrenoceptor agonist
Terbutaline
Albuterol
Salmeterol
Selective B2-adrenoceptor agonist administration
Terbutaline and Albuterol are administered either orally or by inhalation
Salmeterol is given by inhalation only
Selective B2-adrenoceptor agonist timing
Terbutaline and Albuterol Used for acute attacks due to rapid onset
Salmeterol suitable for prophylactic use more than in acute attacks (due to slow onset of action)
When to use Terbutaline and Albuterol
acute attacks
prematur labor
When to use Salmeterol
Prophylaxis
Action of anticholinergics
stimulate cholinergic nerve fibers > (+) muscarinic cholinoreceptors > (+) bronchoconstriction, mucus secretion, broncho vasodilation
Quaternary amine derivative of atropine that is used via inhalation in the treatment of COPD and Asthma
Ipratropium Bromide
Advantages of Ipratropium bromide
- Has a slower onset of action thus suitable for prophylactic use
- More effective in COPD than Asthma
- Effective in patients who have psychogenic asthma and in patients taking beta blockers
- It does not inhibit mucociliary clearance so it does not promote accumulation of secretions in lower airways
A/E of anticholinergics
dry mouth, headache, nervousness, dizziness, nausea and cough
Examples of anti-inflammatory agents
Corticosteroids
Main mechanism of corticosteroids as asthma drug
inhibit inflammatory processes
Disadvantage of corticosteroids
The clinical effects take several hours to several days to develop making it not advisable for quick relief of acute bronchospasm
Most of the agents are used for maintenance treatment of asthma as prophylactic therapy
A/E of Steroids
Systemic Steroids: Adrenal suppresion Cushingoid changes Growth retardation Cataracts Osteoporosis CNS effects/behavioral changes Increased susceptibility to infections
Inhaled Corticosteroids
Generally well tolerated
Either poorly absorbed or rapidly metabolized and inactivated
Most frequent side effects: oral candidiasis, dysphonia, sore throat and irritation
Adverse effects outweigh the benefits from inhaled steroids
Alternative therapies for asthma
Leukotriene Modulator
Example of leukotriene modulators
Zafirlukast, Montelukast,and Zileuton
Most common side effects of Zafirlukast, Montelukast,and Zileuton
Dyspepsia
Main use fo Zafirlukast, Montelukast,and Zileuton
For prophylaxis and chronic treatment of asthma
should not be used for acute episodes
Administration of Zafirlukast, Montelukast,and Zileuton
oral
Contraidications of taking Zileuton
Zileuton inhibits the metabolism of Theophylline
Zileuton has drug reaction with warfarin, terfenadine and propranolol
Zileuton is contraindicated in patients with acute liver disease
Zafirlukast increases plasma concentration of ___ and decreases plasma concentrations of ___
Warfarin ; Theophylline and Erythromycin
Prophylaxis for mild or moderate asthma (4-6 weeks)
Cromolyn sodium and Nedocromil sodium
Admission of Cromolyn sodium and Nedocromil sodium
Inhalation
Advantage of Cromolyn sodium and Nedocromil sodium
Safe in children
Action of Cromolyn sodium and Nedocromil sodium
stabilizes mast cells > prevent mediator release > inhibit effects on irritant receptors and inflammatory cells
Non-pharmacologic Treatment of Asthma
Cessation of smoking Avoidance of environmental exposure Engage in physical activity (swimming) Avoidance of occupation exposures Avoidance of medications that can trigger Asthma attacks Healthy diet
