Resp: Treatment of Asthma Flashcards
Which drugs have a bronchodilator effect but little effect on underlying inflammation?
SABAs
LABAs
CysLT receptor antagonists
Which drugs act as anti-inflammatory agents that reduce airway inflammation?
Glucocorticoids
Cromoglicate
Monoclonal IgE antibodies
Which drugs have both bronchodilator and anti-inflammatory effects?
Methylxanthines
Which drug is given for very mild intermittent asthma? (Step 1)
SABA. e.g. salbutamol
If a SABA is needed more than once a day, which drug is added? (Step 2)
A regular inhaled glucocorticoid. e.g. beclometasone
What is step 3 in the step up pathway of asthma management?
Add a LABA, e.g salmeterol, and monitor benefit.
If good benefit, continue LABA.
If of benefit but not adequate, increase dose of ICS.
If no response to LABA, stop administration increase dose of ICS
If after step 3 of the treatment pathway asthma is still poorly controlled which drugs can be added? (Step 4)
CysLT receptor antagonist, e.g. montelukast
Methylxanthine, e.g. theophylline
Which drug is added in step 5 of the asthma treatment pathway?
oral prednisolone
What is the mode of action of B2 adrenoreceptor agonists? (SABAs/LABAs)
Act as physiological antagonists of all spasmogens - have a bronchodilator effect.
Inhibit mediator release from mast cells + TNF alpha release from monocytes
Increase mucus clearance
What are some of the adverse effects of SABAs?
fine tremor
tachycardia
cardiac dysrhythmia
hypokalaemia
Which form of B2 adrenoreceptor MUST be administered in combination with an ICS?
LABAs
Use as a mono therapy may worsen asthma
Which drug is useful in treatment of nocturnal asthma?
LABAs due to long acting effect
What can happen if B2 adrenoceptors are persistently activated?
Desensitisation of the receptor
The adrenal cortex produces two major classes of corticosteroids: glucocorticoids and mineralocorticoids. Give an example of each.
Glucocorticoid - cortisol (when used as a medication it is called hydrocortisone)
Mineralocorticoid - aldosterone (regulates retention of salt and water by the kidney)
How do glucocorticoids affect gene transcription?
Increase transcription of genes encoding anti-inflammatory proteins + decrease transcription of genes encoding inflammatory proteins.
What cellular effects do glucocorticoids have?
Decrease numbers eosinophils + mast cells + cytokines
Decrease IgE production
Decrease TH2 formation
Decrease mucus secretion
What is a side effect of incorrect use of inhaled corticosteroids?
Oral candidiasis
How are CysLT receptor antagonists such as montelukast administered?
Orally
Give two examples of methylxanthines
Theophylline
Aminophylline (used IV in acute attacks)
What is the mode of action of methylxanthines?
Inhibit phosphodiesterase to increase cAMP - relaxation of bronchial smooth muscle
Also increase mucus clearance and inhibit mediator release from mast cells
What are some adverse side effects of methylxanthines?
Seizures
Dysrhythmia
Hypotension
Which anti-inflammatory drug is more useful in treating atopic asthma in children rather than adults?
Sodium chromoglycate (a cromone)
What is the mode of action of sodium chromoglycate?
Mast cell stabiliser
Which treatment can be given to patients with severe persistent asthma despite maximum therapy?
Omalizumab (Anti-IgE Monoclonal antibody)
What is the mode of action of omalizumab?
Binds to IgE via Fc to prevent attachment to receptors
This suppresses mast cell response to allergens and reduces expression of receptors on inflammatory cells
How is omalizumab administered?
IV
Outline the management of an acute asthma attack
O SHIT MAN Oxygen- 100% through non-rebreather Salbutamol - nebulised Hydrocortisone - IV Ipratropium - nebulised Theophylline - oral (or aminophylline IV) Magnesium sulphate- IV Anaesthetist
