Respiratory Pharmacology Flashcards
Describe Step 1 in the treatment of asthma and name some side effects of the drugs used
Step 1 is for mild-intermittent asthma
GIve short acting beta-2 agonist
Provides symptom relief through reversal of bronchoconstriction
Side effects of beta-agonist use includes tachycardia, palpitations and tremour
Name some short acting beta-2 agonists
Salbutamol
Terbutaline
What happens if beta-2 agonists are used regularly
If used regularly, beta-2 agonists reduce asthma control as regular use causes increased mast cell degranulation in response to allergens causing increased inflammation
Beta-2 agonist used may inhibit mast cell degranulation if used intermittently
Name some inhaled corticosteroids
Beclomethasone dipropionate
Budesonide
Fluticasone
Describe Step 2 in the treament of asthma and how does it help treat asthma
Step 2 is regular preventer therapy using inhaled corticosteriods
Inhaled corticosteriods help improve symptoms and lung function, reduce exacerbation and prevent death
Corticosteroids inhibit eosinophils so help prevent eosinophilic inflammation occuring (eosinophils are a major cause of inflammation in asthma)
Describe Step 3 in the treatment of asthma and why the drugs may be combined into a single inhaler
Add on a long acting beta-2 agonist.
Add in LABA when patient not controlled while using inhaled corticosteroids. LABA not anti-inflammatory
LABA and ICS may be combined for ease of use, increased compliance, less prescriptions to worry about and for safety
Name some long acting beta-2 agonists
Salmeterol
Formoterol
What should be checked before initiating new drug therapy in Step 3 of asthma treatment
Check compliancy
Check inhaler technique
Eliminate trigger factors
What other add ons can be given in Step3/4 of asthma treatment
High dose ICS
Leukotriene receptor antagonists
Methyxanthines
Long acting anticholinergics (LAMAs)
Describe how leukotriene receptor antagonists work and some side effects seen with their use
Leukotriene receptor antagonists inhibits LTC4 action (produced by mast cells and eosinophils) by blocking its receptor
Side effects include: angioedema, dry mouth, anaphylaxis, arthralgia, fever, gastric disturbances, nightmares
Name some leukotriene receptor antagonists
Montelukast
Zafirlukast
Describe how methylxanthines work and some side effects seen with their use. What DDIs do they have
Methylxanthines antagonise adenosine receptors and inhibit phosphodiesterase to increase cAMP in cells
Side effects include: headache, nausea, reflux, arrhythmias, fits
Methylxanthine levels are increased by CYP450 inhibitors, e.g. erythromycin, ciprofloxacin
Name some methylxanthines
Theophylline
Aminophylline
Describe how long acting anticholinergics help in asthma and COPD and the side effects seen with their use
LAMAs help reduce exacerbations in COPD and asthma. They have a small improvement on lung function and symptoms
Are selective for M3 muscarinic receptors
Side effects: dry mouth, urinary retention, glaucoma
Name some LAMAs and whether they are used for COPD and/or asthma
Tiotropium bromide (SPIRIVA) - asthma and COPD
Iprotrapium bromide - asthma and COPD
Aclidinium - COPD
Umeclidinium - COPD
Glycopyrronium - COPD
What types of drugs are used during Step 5 of asthma treatment and name some drugs in each catagory
Anti-IgE - e.g. omalizumab
Anti-IL-5 - e.g. mepolizumab, reslizumab
Describe how Anti-IgE drugs work
Anti-IgE potentially reduce exacerbation rates in patients not controlled on oral steroids
They prevent IgE binding to high affinity IgE receptors but cannot bind to IgE already bound to receptor so prevent cross linking of IgE so mast cells are not activated
Describe how Anti-IL-5 drugs work
Anti-IL-5 reduce eosinophil numbers in peripheral blood and in airways
Reduce rates of severe asthma exacerbations and allow for steroid tapering
What is the treatment of acute, severe asthma
Oxygen
Nebulised salbutamol
PO prednisolone daily for 10-14 days
Nebulised iprotrapium bromide if moderate exacerbation not responding or if acute severe/life threatening
IV aminophylline if no improvement and life threating features not responding to treatment
