Asthma treatment Flashcards
(38 cards)
What is the aim of asthma treatment?
- no daytime symtpoms
- No night time awakening
- No need for rescue medication
- no asthma attacks
- No limitations on activity including exercise
- normal lung function
- Minimal side effects from medications
Who gets an intermittent reliever?
Anyone with diagnosis of asthma
What are the short acting bronchodilators?
- Inhaled short acting B2 agonists
- Inhaled ipratropium bromide
- Theophyllines
When should you consider an inhaled corticosteroid for an asthmatic patient?
- Asthma attack in the past two years
- Using inhaled B2 agonist three times a week or more
- Symptomatic three times a week or more
- Waking one night a week
Explain starting a corticosteroid as preventer therapy
- start at a dose appropriate to the severity of the disease
- titrate the dose to the lowest dose at which effective control of asthma is maintained
- Smoking previous or current reduces the effect of ICS so consider higher doses
What is the mechanism of action of an ICS?
- Bind to activated glucocorticoid receptors
* Suppress multiple pro-inflammatory genes that are activated in asthmatic airways by reversing histone acetylation
What are the indications for an ICS?
- Asthma
* COPD with recurrent exacerbation
What are the side effects of corticosteroids?
- Diabetes
- Osteoporosis
- HTN
- Muscle wasting
- Peptic ulceration
- Cataracts
- Cushings
- Adrenal suppression
- Acute pancreatitis
- Hyperlipidaemia
- Increased appetite
- Salt and water retention
- Immune suppression
What is the first line preventer drug?
Inhaled corticosteroid
What are the non first line preventer therapies for patients taking beta 2 agonist alone
- Leukotriene receptor antagonists
- Sodium cromoglicate and nedocromil sodium
- Theophyllines
If asthma is not adequately controlled with a low dose ICS what are the next steps?
- Recheck adherence, inhaler technique and trigger factors
- First choice add on in adults is an inhaled long acting beta 2 agonist
- This should be considered before upping dose of ICS or adding leukotriene receptor antagonist
What is MART?
- Combination of maintenance and preventer therapy
* Ensures that as the need for a reliever increases, the dose of the preventer is also increased
What should you do if asthma control is inadequate on medium dose of inhaled corticosteroid with a long acting beta 2 agonist or LTRA?
•Increase ICS to high or add LTRA (if not on) or add tiotropium/theophylline
Name 2 LTRAs
- Montelukast
* Zafirlukast
What is the mechanism of action of LTRAs?
- High affinity antagonist of cysteinyl leukotriene receptor inhibiting the action of LT-D4 in smooth muscle cells of the airway and airway macrophages
- Reduces the airway oedema and smooth muscle contraction
Which types of asthma are LTRAs especially useful for?
The phophylaxis of exercise induced asthma and allergic rhinitis
Name a short acting anti-muscarinics
Ipratropium bromide
Name a long acting anti-muscarinic
Tiotropium
What is the mechanism of action of the anti-muscarinics?
- Antagonist of cholinergic M1 and M3 receptors in the lung
- Stops broncho-constriction due to muscarinic receptor activation (connected to Gq-G portions, phospholipase IP3 and intracellular Ca2+)
- On vasculature, M3 activation increases NO production causing vasodilation
What are the indications of anti-muscarinics?
- Asthma
* COPD
What are the side effects of the anti-muscarinics?
- Blurred vision
- Dry mouth
- Urinary retention
- Nausea
- Constipation
What is a side effect specifically of nebuliser ipratroprium?
- Acute angle closure glaucoma
* Use a mouthpiece not a mask
How are anti-muscarinincs excreted?
Renally
What is the mechanism of action of methxanthines?
- Non selective inhibition of phosphdiesterases
- This increases intracellular cAMP
- Bronchial smooth muscle relaxation
- Immunomodulatory effect - improves mucociliary clearance and anti-inflammatory effect (decreases leukotrienes and TNFa)
