Drugs used in Asthma and Allergy Flashcards
What is the difference between intermittent and persistent asthma?
Intermittent Asthma
Symptoms occur 2 or fewer times per week
Oral steroids needed no more than once a year
Persistent Asthma
Needs bronchodilator treatment almost every day
Symptoms prevent patient from participating in normal activities
What are the primary “relievers” in asthma treatment?
B2 agonists used as bronchodilators
What are the short acting B2 agonists?
Albuterol
Terbutaline
Metaproterenol
Bitolterol
What are the long acting B2 agonists?
All end in -erol
Salmeterol
Formoterol
Vilanterol
B2 agonists
MOA
Activate adenylyl cyclase in bronchial smooth muscle
Increases cAMP intracellularly, causes bronchodilation
B2 agonists
Administration
Most often used in metered inhaler.
Could be used in nebulizer (expensive)
Oral- slower onset, more side effects
Parenteral
B2 agonists
Side Effects
How can these be avoided?
Muscle tremors
Tachycardia
Anxiety
Restlessness
Take 1 puff instead of 2 to avoid. Symptoms tend to decrease over time using that drug
Theophylline
MOA
Phosphodiesterase inhibitor used as a long acting bronchodilator
Theophylline
Clinical Use
Long acting bronchodilator used in children under 2yo (because they cannot take inhalational drugs)
Ipatropium and Tiotropium
MOA
Muscarinic antagonists
By blocking muscarinic receptors in the airways, these drugs prevent bronchoconstriction
When would corticosteroids be used in asthma treatment? How are they administered?
Persistent asthma
May be inhalational, oral, or IV
What drugs are used more as asthma “controllers?”
Corticosteroids
Corticosteroids
Onset of Action and Duration of Action
Onset - 3 hrs
Duration 10-12 hrs (inhaled), 6-12 hrs (oral)
Corticosteroids
MOA
Inhibit arachidonic acid synthesis by inhibiting phospholipase A2
Thus, inhibits synthesis and release of leukotrienes and prostaglandins
Corticosteroids Adverse Effects (Short and Long Term)
Short term:
High energy
Hunger
Weight gain
Long term:
Osteoporosis
Cataracts
Myopathy
What is special about drugs like Advair and Symbicort?
They combine long acting bronchodilators and corticosteroids
Cromolyn
Clinical Use
Nebulizer solution given to people with trouble using inhalers
Less effective than steroids and must be given multiple times daily
Cromolyn
MOA
Decreases release of histamines and leukotrienes
Montelukast and Zafirlukast
MOA
Antagonist to leukotriene receptors
Open narrowed airways by decreasing inflammation and mucus production
Zileuton
MOA
Lipooxygenase inhibition
Open narrowed airways by decreasing inflammation and mucus production
Omalizumab
MOA
Monoclonal IgG to human IgE
Prevents IgE binding to mast cell and release of histamines and leukotrienes
What drugs are used to treat allergies in young children (less than 2 yo)?
Cromolyn nasal spray
2nd generation antihistamines (available in liquid form)
What drugs are available to treat allergy in older children and adults (MILD symptoms)?
2nd gen antihistamines
Antihistamine nasal spray
Glucocorticoid nasal spray
Cromolyn nasal spray
What is the most effective treatment for moderate/severe allergies?
Glucocorticoid nasal spray
Glucocorticoid nasal sprays
MOA
Downregulate inflammation by binding intracellular glucocorticoid receptors
Glucocorticoid nasal sprays
Adverse Effects
Nosebleeds
Nasal mucosa irritation
What is the difference between 1st and 2nd gen antihistamines?
1st gen cause significant sedation. They are lipophilic and can cross the BBB
2nd gen avoid the CNS symptoms, but may cause weight gain
Decongestants
Adverse Effects
HTN
Insomnia
Irritability
HA
