Drugs for Respiratory Tract Flashcards
Antiinflammatory Drugs
Corticosteroids: Beclomethasone Triamcinolone Budesonide Fluticasone
Mast cell stabilizers:
Cromolyn Sodium
Lodoxamide
Nedocromil
Leukotriene inhibitors:
Montelukast
Zafirlukast
Zileuton
Phosphodiesterase type 4 inhibitors:
Roflumilast
Corticosteroids - MoA
-Suppress the activation of T-lymphocytes by interleukins and nuclear factor KB
-Suppress production of cytokines by activated T-cells
-Decrease the release of histamine, prostaglandins and leukotrienes by increased transcription of annexin-1
(–>inhibit phospholipase A2)
-Stabilize lysosomal membranes of neutrophils
-Cause vasoconstriction by inhibiting phospholipase A2 (prostacyclin’s)
-They decrease activation of macrophages
Corticosteroids - Clinical use
Asthma
Allergic rhinitis
(long term basis to prevent asthmatic attack rather than treatment of acute bronchospasm)
Corticosteroids - Adverse effects
Oral candidiasis (thrush) Growth retardation
Mast cell stabilizers - MoA
They block calcium influx into mast cells and thus stabilize the plasma membranes of mast cells and eosinophils and thereby prevent degranulation and release of histamine, leukotrienes, and other substances that cause airway inflammation. They do not interfere with the binding of IgE to mast cells or with the binding of antigen to IgE.
Cromolyn Sodium - Clinical use
Asthma,
Allergic rhinitis and
Seasonal (Vernal) conjunctivitis.
Given orally to treat mastocytosis, ulcerative colitis and food allergy.
(Long-term prophylaxis of asthmatic bronchoconstriction and allergic reactions, but have no role in treatment of acute bronchospasm)
Cromolyn Sodium - Adverse effects
Throat irritation
Cough
Bronchospasm (Administration of beta2 agonist can prevent this)
Lodoxamide and Nedocromil - Clinical use
Ophthalmic solution to treat ocular allergies;
-Seasonal (vernal) keratitis and conjunctivitis
Lodoxamide and Nedocromil - Adverse effects
Ocular discomfort
Montelukast and Zafirlukast
- MoA
Cysteinyl leukotrienes C4, D4, and E4 activate the type 1 cysteinyl leukotriene receptor (CysLT1) and thereby increase recruitment of leukocytes, stimulate mucus secretion, increase vascular permeability increase collagen, and cause smooth muscle proliferation and contraction. These effects lead to airway inflammation and to sustained bronchoconstriction. These drugs compete with cysteinyl leukotrienes for the CysLT1 receptors and inhibit both early and late phases of bronchoconstriction induced by antigen challenge. However, they do not block the effect of leukotriene B4, which appear to be important in severe asthma and asthma exacerbation.
Montelukast and Zafirlukast
- Clinical use
Allergic asthma including
Aspirin-sensitive asthma, and prevention of
Exercised-induced asthma (Less potent than corticosteroids, but may be given to pt that are unable/unwilling to take steroids, or not adequately controlled by inhaled steroids alone)
Montelukast and Zafirlukast
- Adverse effects
Allergic granulomatous vasculitis (Churg-Strauss syndrome)
Hypersensitivity reactions
Liver injury
Zafirlukast - Interactions
Zafirlukast inhibits CYP enzyme and may elevate plasma level of phenytoin, warfarin, felodipine, lovastatin, and triazolam.
Zileuton - MoA
Inhibits 5-lipoxygenase and blocks the formation of all leukotrienes, including LTB4. Because the CysLT1 receptor antagonists do not block the leukocyte chemoattractant and other effects of LTB4, zileuton might be more effective in severe cases of asthma.
Zileuton - Clinical use
Prophylaxis and treatment of asthma in adults and children above 12 years.
