Respiratory Drugs Flashcards
What are the five criteria for good asthma control?
- Minimal symptoms
- Minimal need for relieving meds
- No limitation to physical activity
- No exacerbations
- Normal lung function tests
State two things that need to be checked before stepping up asthma treatment
- Complience with existing therapies
- Inhaler technique
- Elimination of trigger factors
- Make sure the pt isn’t on ACEIs or beta-blockers
What is step one of asthma control?
Short-acting beta2 agonist when required
Name two examples of short-acting beta2 agonists
Salbutamol
Terbutaline
What is the MoA of short-acting beta2 agonists?
Reverses/prevents bronchoconstriction
Why shouldn’t short-acting beta2 agonists be used too frequently?
Reduce asthma control by increaseing mast cell degranulation in response to allergens
State two side effects of short-acting beta2 agonists
Tachycardia
Palpitations
Tremor
What is step two in the asthma treatment pathway?
Regular preventer therapy - inhaled corticosteroids
State the four criteria for starting regular inhaled corticosteroids
- Using a beta2 agonist 3 or more times a week
- Symptoms 3 or more times a week
- Waking once or more a week
- Exacerbation of asthma requiring oral steroids in the last two years
Name an inhaled corticosteroid used in asthma
Beclomethasone
What are the three mechanisms by which inhaled corticosteroids improve symptoms and lung function?
- Increase in beta2 receptors
- Decreased eosinophils
- Decreased inflammatory mediators
What is step three in the asthma treatment pathway?
Long-acting beta2 agonist
Name two long-acting beta2 agonists
Salmeterol
Fomoterol (more potent and more effective)
What must long-acting beta2 agonists be prescribed with?
Inhaled corticosteroid
Can get combined inhalers
What are the four options in step four in the asthma treatment pathway?
- High-dose inhaled corticosteroids
- Leukotriene receptor antagonist
- Methylxanthines
- Long-acting anticholinergics
Name a leukotriene receptor antagonist
Montelukast
Zafirlukast
What is the MoA of leukotriene receptor antagonists?
Mast cells release LT-C4 which causes bronchoconstriction, mucus secretion, mucosal oedema and recruitment of inflam cells.
By blocking the LT receptor, the drugs prevent this from happening.
Roughly how many patients find leukotriene receptor antagonists useful as an add-on therapy?
15%
State two side effects of leukotriene receptor antagonists
Angioedema Dry mouth Arthralgia Fever Nightmares
Name a methylxanthine
Theophylline
Aminophylline
What is the MoA of methylxanthines?
Antagonise adenosine receptors
Anti-inflammatory and broncho-protective
State two adverse effects of methylxanthines
Headache
Nausea and reflux
Arrhythmias
Fits
Has many DDIs
Name a long-acting anticholinergic
Tiotropium bromide (SPIRIVA)
What is the MoA of long-acting anticholinergics?
M3 receptor antagonist to prevent parasympathetic bronchoconstriction
