Pharm 16 Flashcards
Identify airway insults that can contribute to the development of the asthmatic airway
Allergens
Microbes
Viruses
Environmental factors
Identify the physiological changes in the airway smooth muscle and extracellular network
Fibrotic
Increased cell size (hypertrophy)
Increased cell numbers (hyperplasia)
Describe the contribution of leukotrienes to respiratory symptoms of asthma and anaphylaxis
Beta-2 receptor stimulation
- Smooth muscle = relaxation
- Mast cell membrane = stabilization
- Skeletal muscle = stimulation
Effects of physiologic cholinergic input to bronchial smooth muscle.
- M1 and M3 = bronchoconstriction
- M2 = bronchodilation
Effects of physiologic adrenergic input to bronchial smooth muscle.
- Activates the G proteins within the cell membranes of the smooth muscle causing relaxation
Locations of beta-adrenergic receptors in the body and the anticipated pharmacologic effects of agonizing the beta-2 receptor.
Bronchial smooth muscle - Bronchodilation
Uterine muscle - Uterine relaxation (toxolysis)
Clinical applications of the short-acting beta-agonists
- “rescue” medications
- Mild, intermittent asthma or in patients with just exercise-induced bronchoconstriction
- Needing a rescue medications more than twice a week indicated asthma is not well controlled
- Ex. Albuterol
Clinical applications of the long-acting beta-agonists
- Not rescue medications
- Not be used as the only controller therapy
- Increases risk of asthma-related death and asthma-related hospitalizations
- Can be acceptable as the only “controller drug” in COPD
Describe the mechanism of action of muscarinic antagonist drugs used as bronchodilators
Block acetylcholine (bronchoconstriction) resulting in bronchodilation especially in COPD
Describe the potential benefits of muscarinic antagonist drugs used as bronchodilators
Many different ways to take medications - inhalation in powder or mist
Proper inhalation technique of metered-dose HFA inhalers (MDIs
- Shaking (dissolving of the crystals)
- Priming (if first use, dropped, or not used for > 7 days)
- Time interval between inhalations
- Inhaling slowly and deeply
Proper inhalation technique of Dry powder inhalers/diskus (DPIs), Handihaler, Ellipta
Flip open to put powder into a chamber and then inhale the powder
Proper inhalation technique of Respimat
spin to put mist into the chamber and press button to cause the release of mist and then inhale the mist
Recognize when the use of alternative or additional inhalation devices may be helpful/necessary
- The most effective “controller” asthma medications available are the glucocorticoids
- Inhibit many immune cells
- Regular use of an ICS as a controller
List the adverse effects of glucocorticoid (AKA, corticosteroids) use; particularly with long-term systemic glucocorticoids
- Infection risk
- Risk for developing diabetes, osteoporosis, weight gain, abnormal fat distribution
- Adrenal suppression (crisis)
- Hypertension
- Glaucoma, cataracts
Inhaled corticosteroids and inhibition of growth in children.
- Reassure
- Studies have shown that it does not cause growth impairment
- Reach their target adult height despite initial growth retardation
- Slowed growth velocity in the first year only
- Same growth velocity for 2-4 years
- 0.5 cm less than the average for the control group
Alternative controller medicines if not well controlled or do not tolerate ICS
Cromolyn, LTRA or theophylline
Explain the MOA and clinical role/benefit of Theophylline
- Controller medication
- Metabolized by CYP1A2
- Well absorbed widely distrubuted, crosses BBB
- apnea and bradycardia in premature babies
Explain the potential toxicity of theophylline
- Smoking induces CYP1a2 so toxicity more likely to occur
- Nausea/vomiting/abdominal pain, coarse muscle tremor
- Seizures, hypotension, and dysrhythmias
- Death occurs, d/t intractable ventricular dysthymias
Leukotriene receptor antagonists (LTRA)
- Prophylaxis and chronic treatment of asthma in patients >12 months
- Acute prevention of exercise-induced bronchoconstriction in patients >6 years
- Relief of symptoms of allergic rhinitis
Leukotriene receptor antagonists (LTRA) ASEs
Headache, dyspnea, sinusitis, nausea, diarrhea, myalgia, leukopenia
Leukotriene receptor antagonists (LTRA) caution use in
- Neuropsychiatric events
- Eosinophilic conditions
- Phenylketonuria
Omalizumab (monoclonal antibodies)
- Only for refractory “allergic asthma”, eosinophilia
Omalizumab (monoclonal antibodies) caution use in
- Should only be administered in a healthcare setting by providers who are prepared to identify and treat anaphylaxis
Omalizumab (monoclonal antibodies) black box warning
- First 3 injections, monitored in office for 2+ hours, delayed hypersensitivity can also occur
Cromolyn (mast cell stabilizer)
- used for asthma tx
- caution: not a bronchodilator, reduces hyper-reactivity of the bronchi
Roflumilast (PDE- 4 Inhibitor) use
- COPD exacerbation
- Once daily
- But $$$
- SE: neuropsychiatric effects, decreased weight, nausea, diarrhea
