Asthma Flashcards
Common asthma triggers
5 majour indoor triggers Molds Dust mites Cockroaches Animal dander Second hand smoking
What are the acute symptoms of asthma
Bronchospasm and wheezing
How are acute symptoms of asthma reversed
With bronchodilators
How is asthma inflammation and exacerbations controlled
By anti inflammatory drugs
How can we treat airway remodelling
No treatment
What are the advantages of inhaled therapy
Direct delivery of the drug to the site of action
Rapid onset of action
Lower dose to produce desired effects
Minimise systemic adverse effects
What are the inhalation devices
Devices used to make an aerosol out of the drug solution
What are the types of inhalation devices
Inhaler - generate aerosols of solid particles
Nebulizer - generate aerosols of liquid particles in gas cloud
What to avoid deposition of solid particles from an inhaler in the mouth
By using a spacer
How is the drug absorbed from a dry powder inhaler
Drug is absorbed on a lactose carrier
What’s the preferred deliver in asthma treatment (rescue medication)
Low dose ICS + formoterol
What is the optimal route of administration for corticosteroids in inflammatory lung disease
Inhaled
What are inhaled corticosteroids used for
Used in asthma prophylactic therapy not to reverse acute asthma attack symptoms
What’s the best combination of corticosteroids in asthma
ICS + formoterol
List of ICS used in asthma
All are prodrugs
Beclomthasone
Dipropionate
Ciclesonide
How are the prodrugs of ICS activated
They admire metabolised in to active form by esterases in the lung
Which ICS is metabolised in the liver
Prednisone-> prednisilone
What are the characteristics that enhance the efficacy of inhaled ICS
Lung pulmonary residence time due to
- lipophilicity
- lipid conjugation
What are the ICS with the best lipophilicty
Ciclesonide
What are the ICS with the worst lipophilicty
Budesonide
What are the ICS with the best lipid conjugation
Budesonide
What are the ICS with the worst lipid conjugation
Ciclesonide
What are the topical adverse effects of Inhaled ICS
Dry mouth
Pharyngeal irritation
Increase frequency of oral condidiasis
How to reduce the topical adverse effects of ICS
Proper technique, using spacer and rinsing mouth after inhalation
What ICS is used in long term treatment of asthma
Inhaled ICS
What ics is used in acute asthma exacerbations and chronic severe asthma
Oral corticosteroids like
Prednisone
Prednisilone
Methyprednisolone
What ICS is used in severe acute asthma
I.V corticosteroids like
Hydrocrotisone
Methylprednisilone
Mode of administration of leukotrienes modifying drugs - what’s their effect on CYP450
Oral - they inhibit CYP450
What are leukotrienes
Receptor antagonists
What is montelukast and zafirlukast and what’s their drug interactions
Leukotrienes synthesis inhibitors
Interaction with warfarin
Zileuton mechanism of action and drug interactions
Inhibit 5-LOX
Interacts with theophylline and warfarin
What is leukotrienes treatment ineffective in
Acute bronchospasm
What is leukotrienes treatment effective in
In aspirin and excercise asthma
What can leukotrienes do to B2 agonists effect
Enhances the effect
What type of asthma are leukotrienes used for
Mild to severe asthma
What leukotrienes is approved in children over 6 months
Montelukast
What leukotrienes is used in children over 5 years
Zafirlukast
What does corticosteroids inhibit
Phospholipase A2
Mechanism of action of zafirlukast and montelukast
Bind to leukotriene receptors
Zileuton mechanism of action
Inhibits 5 lipooxygenase
What are the similarities between leukotrienes and corticosteroids uses
They can both be used as a controller but not for acute bronchospasm
What is the B2 receptors agonists actions
Relaxation of bronchi smooth muscle and decrease airway resistance
List SABA
Short acting B agonist
Albuterol
Fenoterol
What are SABA used for
active inhalation treatment of bronchospasm ( with low dose ICS - budesonide)
SABA onset and duration of action
1-5 mins quick
Lasts for 2-6 hours short
What are SABA most effective in
Most effective drugs in relaxing airway smooth muscles
LABA
Long acting B agonist
Formoterol
Slameterol
What are formoterol and salmeterol used for
Both are used for prevention of asthmatic attacks since they are long acting
BUT.
Formoterol can be used for relief from asthma attacks
How often is LABA given
It’s given twice daily by inhalation for long treatment of asthma
What are LABA USED FOR
Useful in
- preventing nocturnal asthmatic attacks
- prevent Late phase of allergen induced bronchoconstriction
Why shouldn’t LABA be used alone
Masks the symptoms and lacks anti inflammatory action
What should LABA be used with
ICS
LABA adverse effects
Tremors and tachycardia
What’s the corticosteroids and B2 agonist drug interactions
Corticosteroids prevent the desensitisation of B2 receptors and increase synthesis of B2 receptors
What’s the rescue dose of LABA + ICS
4,5 ug , 160 ug or 4.5 ug, 80ug
E.g-> formoterol + budesonide
Other name for methylxanthines
Theophylline
Theophylline mode of administration
Oral
Theophylline mechanism of action
Inhibits phosphodiesterase -> causing an increase in CAMP with in the cell leading to smooth muscle relaxation
What’s wrong with theophylline therapeutic index
Has a narrow therapeutic index 5-15 mg/ml
Theophylline indications
Bronchodilator in COPD
Theophylline metabolism
Metabolised in the liver
How do anticholinergic agents prevent contraction
Antagonist of M3 receptors in the bronchial smooth muscles
Where are parasympathetic pathways more important
In bronchospasm than in some asthmatics
What are anticholinergic agents used with
Used with ICS and LABA
CANT REPLACE LABA
Anticholinergic agent effect on COPD AND ASTHMA
COPD»_space; Asthma
Can ipratropium work alone
It is ineffective in reversing bronchospasm on its own
Ipratropium onset and duration of action
15 mins
6 hours
Tiotropium onset and duration of action
30 mins
More than 24 hours
What’s a good combination with ipratropium
Ipratropium with a SABA usually with FENOTEROL
Instead of either alone
Mechanism of action of omalizumab
Antibody against IGE. Blocks it from binding to mast cells
Omalizumab is used in which patients
Patients with sensitisation to perinnial aeroallergens - frequent asthma exacerbation
IL 5 antagonists suffix
Zumabs but not omalizumab
What does IL 5 do
Recruitment of eosinophils
What are IL5 antagonists indicated for
Given for eosinophilic asthma as it decreases the production and survival of eosinophils
