1.
Prof. Amol Deore
Department of Pharmacology
MVPs Institute of Pharmaceutical Sciences, Nashik
ANTIASTHMATIC AGENTS

2.
Bronchial asthma
•Bronchial asthma is an allergic inflammatory disease
of airways characterised by repeated episodes of
bronchospasm and bronchial obstruction
accompanied by increased secretion, mucosal
edema and mucus plugging.

3.
Bronchial asthma is characterised by dyspnoea and wheeze due to
increased resistance to the flow of air through the bronchi.
Bronchospasm, mucosal congestion and oedema result in increased
resistance.
The tracheobronchial smooth muscle is hyper-responsive to various
stimuli like dust, allergens, cold air, infection and drugs.
These trigger-factors trigger an acute attack.

4.
Inflammation is the primary
pathology.

5.
Antigen-antibody interaction on the
surface of mast cells cause:
•Degranulation of mast cells releasing stored
mediators of inflammation
•Synthesis of other inflammatory mediators
(autacoids) which are responsible for
bronchospasm, mucosal congestion and oedema

6.
Antigen antibody reaction

7.
Clinically 2 types of asthma are identified.
Extrinsic asthma Starts at an early age, occurs in
episodes; the patient has a family history of
allergies.
Intrinsic asthma Starts in the middle age and
assumes chronic form. There is no family history of
allergies.

8.
Drugs used in the bronchial asthma may
be grouped as follows.

9.
Bronchodilators
1. β-2 Sympathomimetics: Ex. Salbutamol, Terbutaline, isoproterenol, isoprenaline,
Salmeterol, Bambuterol Formoterol, Rimiterol, Bitoterol, Ephedrine and adrenaline.
2. Anticholinergics (parasympatholytics):
Ex. Ipratropium, Tiotropium, oxitropium and atropine.
3. Methylxanthines: Ex. Theophylline, Aminophylline, Doxophylline, Diprophylline,
enprophylline.
4. H-1 Antihistamines: mepyramine, diphenhydramine
B} Leukotriene antagonists
Ex. Montelukast, Zafirlukast, Ablukast, Pranlukast.
C} Mast cell stabilizers
Ex. Chromolyn Sodium, Nodocromil, Ketotifen.
D} Corticosteroids
Ex. Hydrocortisone, Prednisolone, Beclomethasone, Fluticasone, triamcinolone,
Dexamethasone, Mometasone
E} Anti-IgE monoclonal antibody
Ex. Omalizumab, Mepolizumab, Reslizumab, Benralizumab, Lebrizumab, ustekizumab

10.
•Salbutamol, Terbutaline,
isoproterenol, isoprenaline,
Salmeterol, Bambuterol
Formoterol, Rimiterol, Bitoterol,
Ephedrine and adrenaline
BETA
SYMPATHOMIMETIC
DRUGS

11.
Selective β2 agonists are the most commonly used
bronchodilators as they are the most effective, fast-acting,
convenient and relatively safe bronchodilators.
They are available as metered dose inhalers, nebulizers,
injections and also tablets for oral use.
The proper technique in using the inhaler should be taught.
‘Spacers’ can be used in children and adults who cannot follow
the right technique of inhalation

12.
Mechanism of action
• β-2 Sympathomimetics stimulate β receptors leads to relaxation
of smooth muscle in the lung, and dilation and opening of the
airways.
• β-2 Sympathomimetics activate adenylyl cyclase enzyme which
converts ATP in to cAMP which show potent bronchodilation.
• The increased cAMP in mast cells inhibits the release of
inflammatory mediators. They also reduce bronchial secretions
and congestion
ATP adenylyl cyclase cAMP Bronchodiation

13.
Route: oral metered pump, inhaler, nebulizer

14.
STATUS ASTHMATICUS
Acute severe asthma or status asthmaticus is an acute
exacerbation (emergency).
It is a medical emergency; may be triggered by an acute
respiratory infection, abrupt withdrawal of steroids after
prolonged use, by drugs, allergens or emotional stress.

15.
SYMPTOMS
• Chest tightness
• Shortness of breathing
• Dyspnoea
• Extreme wheezing
• Cardiovascular collapse and respiratory collapse
• Increased pulse and breathing rate
• Impossible of speak more than few words
• Inability to speak even a complete sentence

16.
Management
Hospitalization
artificial respiration and ventilator
Bronchial lavage to remove mucus plug
Intravenous therapy
salbutamol
aminophylline
corticosteroids
Mast cell stabilizers
Broad spectrum antibiotics
Antianxiety
Sedatives
IV fluid therapy

17.
Treatment
• Hospitalize the patient
• Multiple therapies are used to reverse the effect of status asthmaticus.
• Bronchial lavage to remove mucus plugs
• Intubation and mechanical ventilation,
• Adrenaline 0.2-0.5 ml subcutaneously (1:100,000)
• Aminophylline IV
• Hydrocortisone hemisuccinate IV 100 mg stat followed by 100 mg every 8
hours infusion followed by a course of oral prednisolone.
• Oxygen inhalation.

18.
• Nebulized salbutamol + ipratropium bromide (0.5 mg) inhalations driven by
O2.
• Beta 2 stimulant salbutamol iv (2.5–5 mg)
• Salbutamol/terbutaline 0.4 mg i.m./s.c. may be added, since inhaled drug
may not reach smaller bronchi due to severe narrowing/ plugging with
secretions.
• Treat chest infection with intensive broad spectrum antibiotic therapy
(amoxicillin)
• Sedative drugs diazepam used.
• To correct dehydration and acidosis with saline+ sod. bicarbonate/lactate
infusion

19.
Thanking You.