Drugs For Treating Asthma Flashcards
What is asthma?
- chronic inflammatory disease of the airway
- results in obstruction of the airways from bronchoconstriction, edema, and excessive mucus production
Why are NSAIDs typically ineffective in treating inflammation in repiratory system, but corticosteroids are?
Asthma is caused by leukotrienes which is a separate branch off of arachidonic acid. Corticosteroids act on phospholipase A2, whereas NSAIDs inhibit later on in the process to COX.
Name some factors that can precipitate an asthma exacerbation:
- pet allergens
- dust mites
- fungal spores
- infection
- tobacco smoke
- pollen
- chemical exposure
- comorbid conditions
- cold temperatures
- NSAIDs
- exercise
What is EIB?
- exercise induced bronchospasm
- can be a symptom of asthma, but can have bronchospasm and no asthma
- if it only happens in exercise, it’s usually EIB
What is NSAID induced asthma?
- NSAIDs or aspirin can trigger asthma in those that have severe asthma
- less likely in those with mild or moderate asthma
What is bronchospasm?
- reversible airway obstruction caused by spasm of the smooth muscles of the bronchial walls
- non inflammatory, meaning an anti-inflammatory will not help.
What are the 2 categories of asthma/EIB medications when categorized by therapeutic intention?
- quick-relief therapy: “rescue” medications, used for acute symptoms
- long-term therapy: decrease chronic inflammation, decrease frequency of acute attacks
What are the 2 categories of asthma/EIB medications when categorized by pharmacological activity?
- bronchodilators: relax bronchial smooth muscle, open airways
- anti-inflammatory drugs: decrease chronic inflammation
How are quick-relief drugs used?
- treat symptoms in an acute attack
- prevent an imminent attack
- taken when needed, not on a routine basis
- can also be taken prophylactically before exercise if EIB
- every asthma patient should have a quick-relief drug available
Name 3 quick-relief drugs:
- short acting beta2 agonists (SABA)
- anticholinergics
- systemic corticosteroids
What do Beta 1 and Beta 2 do?
- Beta 1: receptors found in heart and kidneys (can have impact on BP and blood volume). Can be considered a performance enhancing drug.
- Beta 2: dilating bronchioles
Most SABA are made up of….
A mix of Beta 1 and Beta 2.
How do short acting beta2 agonists work? What are some examples of it?
- rapid onset (5 min or less)
- short duration (up to 6 hours)
- results in broncodilation
- if needing quick-relief drugs daily, they are not being managed well and need long term medications. Tolerance can be developed to both.
- ex. Albuterol/Salbutamol - Albuterol (Ventilin) most common
Side effects of short acting beta2 agonists (SABA):
Most effects are local because of inhalation, less risk of the side effects below:
- short term muscle tremor (can effect sport performance)
- hyperglycaemia
How do anticholinergics work? Give an example.
- inhibit cholinergic receptors of the parasympathetic nervous system
- not commonly used in asthma treatment
- specifically blocks the action of neurotransmitter acetylcholine. Blocks mucus production and causes broncodilation
- Can be used for asthma (not as common) and EIB. Not nearly as effective as SABA
- ipratropium - often used in combination with SABA
How does systemic corticosteroids for asthma work?
- typically oral administration
- most commonly prednisone
- short course
- risks/adverse effects
Name 4 long-term therapies for asthma.
- inhaled corticosteroids
- long acting beta agonists (LABA)
- mast cell stabilizers
- leukotriene modifiers