BScN DRUGS USED IN ASTHMA and hypersensitivity.pptx

Asthma

1. DRUGS USED IN ASTHMA DR.FOUZIA

2. ASTHMA Asthma is a chronic disorder of airways characterized by airway obstruction hyper responsiveness inflammation. Symptoms Shortness of breath chest tightness associated with coughing and excess sputum production.

3. CLASSIFICATION OF DRUGS FOR ASTHMA Bronchodilators (Relievers) 1- β -Agonists (β2-selective) Short-acting Albuterol, Terbutaline Phosphodiestrase (PDE) inhibitors Aminophylline Antimuscarinic agents Ipratropium bromide, Tiotropium

4. CLASSIFICATION OF DRUGS FOR ASTHMA Anti-inflammatory (Controllers) 1-Corticosteroids Inhalational Beclomethasone, Budesonide, Fluticasone, Systemic Hydrocortisone, Prednisolone, Prednisone 2-Long-acting bronchodilators Salmeterol Formeterol

5. CLASSIFICATION OF DRUGS FOR ASTHMA Prophylactic drugs: 1-Mast cell stabilizers Cromolyn, Nedocromil 2-Leukotriene pathway inhibitors 1-5-Lipoxygenase inhibitor Z ileuton 2-LTD4-receptor antagonists Zafirlukast Montelukast

6. ROUTES OF ADMINISTRATION IN ASTHMA 1-Inhalational Delivery devices Metered- dose inhalers Space chambers Dry powder inhalers Nebulizers 2-Oral route 3-Parenteral route

7. β2-AGONISTS Produce bronchodilation Mechanism of action: Binding β 2  ↑ cAMP  Bronchodilation Inhibit release of mediators from mast cells Route: Inhalation, Oral (Albuterol,Terbutaline), S/C (Terbutaline) Use in asthma 1-Occasional symptoms  as needed 2-Nocturnal symptoms  more than twice a week 3-Acute severe asthma combine with ICS

8. METHYLXANTHINE (PDEI) Caffeine (Coffee) Theophylline (tea) Theobromine (Cocoa) Mechanism of action of Theophylline 1-Inhibition of PDE Relaxation of smooth muscles of bronchi

9. METHYLXANTHINE (PDEI) Pharmacological effects: 1-Respiration Bronchodilation 2-CNS ↑ alertness , ↓ fatigue, nervousness, insomnia 3-CVS ↑ heart rate and force of contraction 4-Skeletal Muscle Improve contractility of skeletal muscle, reverse fatigue of diaphragm in patients with COPD

10. METHYLXANTHINE (PDEI) A/R Headache Nausea Vomiting Abdominal discomfort Restlessness Behavioral disturbances, difficulty in learning(school children) Cardiac arrthymias Seizures

11. ANTIMUSCARINIC Bronchodilation Mechanism of action Block M3 receptors A/R Rebound ↑ airway resistance Bitter taste of ipratropium Precipitation of glaucoma

12. CORTICOSTEROIDS Anti-inflammatory effect ↓Bronchial hyper reactivity, & frequency of asthma exacerbations Anti-inflammatory Effects in Asthma 1-Inhibit infiltration by lymphocytes, eosinophils , mast cells. 3-Inhibit inflammatory cytokines from TH2 cells 4-↓ A irway edema 5-Potentiate effects of β agonists on bronchial smooth muscles

13. MAST CELL STABILIZERS Mechanism of action Inhibit histamine release from mast cells and eosinophilic recruitment Advantages 1-Prophylactic use 2-↓ need for ICS 3- Excellent safety profiles

14. LEUKOTRIENE PATHWAY INHIBITORS LTC4 and LTD4 Bronchoconstriction Mucosal edema Zileuton: Inhibition of 5-lipoxygenase Monteleukast : Antagonist of LTD4-R USES 1-Prophylaxis of asthma ↓frequency of asthma exacerbations

15. MANAGEMENT OF ASTHMA 1-Educate patient to avoid allergens 2-Prophylaxis of asthma Mast cell stabilizers Cromolyn Nedocromil 3-Acute asthma: 1-High flow O2 to maintain O2 saturation above 90% 2-High dose of Short acting beta agonist (SABA) by nebulizer 3- Salbutamol +Ipratropium bromide by O2 driven nebulizer 4-Aminophyllin infusion 5-Intubate the patient for assisted ventilation