The document discusses bronchial asthma as a chronic inflammatory disorder of the airways characterized by symptoms such as breathlessness, coughing, and wheezing. It covers various aspects including epidemiology, risk factors, diagnosis, and treatment options such as bronchodilators like salbutamol and adrenaline. Complications from poorly-controlled asthma are also highlighted, emphasizing their impact on the quality of life.

1. Lower Respiratory Tract
Disorder - Bronchial Asthma
Dr. SARITA SHARMA
ASSOCIATE PROFESSOR
DEPARTMENT OF PHARMACOLOGY

2. CONTENTS
1) INTRODUCTION
2) EPIDEMIOLOGY
3) ETIOLOGY & RISK FACTORS
4) SIGNS & SYMPTOMS
5) PATHOPHYSIOLOGY
6) DIAGNOSIS
7) TREATMENT
8) COMPLICATIONS

3. Anatomy of Respiratory System

4. Introduction:
 The National Asthma Education & Prevention Program
(NAEPP) define asthma as:
 It is a chronic illness of the lungs & respiratory
system.
 It is an inflammatory disorder of airways in which
many cells & cellular elements undergo inflammation.
 It is characterized by recurrent episodes of
Breathlessness, Coughing, Chest tightness and
Wheezing.
 These episodes usually associated with airflow

5. Narrowing of Bronchial
Lumen

6. Epidemiology:
 Bronchial asthma is common and prevalent
worldwide.
 In United States about 4% of population suffering
from asthma has been reported every year.
 It occurs at all age group people, but 50% of asthma
cases develop after the age of 10 years.
 In adults, both males & females are affected equally
but in children, occurrence rate of boys & girls is 2 :
1 ratio.

7. Etiology and Risk factors: Asthma Triggers include
 Irritants in the air: Smoke, chemical fumes, strong
odours.
 Indoor allergens: Pet dander and dust mites.
 Outdoor allergens: Pollen from grass, trees and weeds.
 Weather conditions: Cold air & extremely windy
weather.
 Upper respiratory infection: Cold, flu, sinusitis,
Pharyngitis.
 Certain drugs: Aspirin, Beta blockers, Ibuprofen,

8. Signs & Symptoms:
 Cough: It is chronic that occur during exercise and is
nocturnal in nature with the presence of phlegm
(sputum).
 Respiratory: Difficulty breathing, Breathing through
the mouth, Tachypnea, Dyspnea, Wheezing and
Frequent respiratory infections.
 Also common: Anxiety, Early awakening, Throat
irritation, Chest tightness & Tachycardia.

9. Pathophysiology: Major characteristics of asthma occur
due to Bronchospasm, Hypersecretion & Airway
Inflammation. It is associated with the activation of
immunoglobulin E (IgE) antibodies. Mast cells and
macrophages are activated. Asthma patients have high
viscosity expectorated mucus.

10. Diagnosis:
 Clinical manifestations, history, physical
examination & laboratory tests.
 Radiographic examination.
 Pulmonary function tests; it helps to evaluate the
severity of lung diseases.
 After the inhalation of β2 agonist drugs, If FEV1 /
FVC is less than 80%, Spirometry test confirms
presence of obstruction.

11. Treatment:

12. 1) SALBUTAMOL:
 It is a potent bronchodilator drug that acts directly on
beta 2 receptors of bronchial smooth muscles.
 Salbutamol has less cardiac stimulant effect and so can
be used safely in patients suffering from cardiac diseases.
 It has long duration of action due to resistance developed
by inactivating COMT enzyme (Catechol–O–Methyl-
Transferase).
 It is administered by oral, parenteral and inhalation
routes.
DOSE: 2 to 4 mg by oral route.

13. 2) ADRENALINE:
 It is a potent drug having a significant role in relieving
acute asthma attack and pulmonary congestion.
 Adrenaline acts by stimulating beta receptors of bronchial
smooth muscles.
 Side effects include ventricular tachycardia and
ventricular fibrillation.
 Adrenaline should not be given to patients suffering from
cardiac asthma, hypertension and hyperthyroidism.
 Dose: 0.2 to 0.5ml of 1 in 1000 solution by S.C. injection.

14. 3) THEOPHYLLINE:
 It is a weak bronchodilator and acts synergistically
with beta adrenergic agonist drugs there by
producing a direct relaxant effect of bronchial
smooth muscles.
 Usual route is oral or slow I.V. injection given at a
dose of 250 to 500 mg.
 It is effective when adrenaline fails to relieve acute
attack or if the patient is resistant to adrenaline.
 Repeated use of theophylline in children may
produce disturbance in learning and sleep.

15. 4) EPHEDRINE:
 It is a sympathomimetic drug which acts on both alpha
and beta adrenergic receptors. It is a week
bronchodilator.
 It causes insomnia. This can be prevented by
combining Ephedrine with Phenobarbitone.
5) KETOTIFEN:
 It acts by inhibiting airway inflammation that is induced
by Platelet Activating Factor (PAF).
 It has antihistaminic effect.
 Side effects include Drowsiness and Dry mouth.

16. 6) DISODIUM CHROMOGLYCATE:
 It is a synthetic compound which acts by inhibiting the
phosphodiesterase enzyme thereby preventing mast
cell degranulation.
 It also prevents the release of spasmogenic
substances like histamine and serotonin, But it does
not have antihistaminic effects.
 It is poorly absorbed on oral administration and do
not produce any adverse effect except local irritation.
 Dose: 20 mg given by inhalation 3 to 4 times daily by
means of 'spinhaler'.

17. Complications:
Poorly-controlled asthma can have a negative
effect on quality of life. Complications include
Pneumothorax, Pneumopericardium, Pneumonia,
Pulmonary interstitial emphysema, Cardiac
arrhythmias, Myocardial infarction, Electrolyte
imbalances, Lactic acidosis, Hyperglycemia.