1. Anti asthmatic drugs

2. Asthma
• Asthma is a disease associated with inflammation of the
airway wall. It is characterised by hyper responsiveness of
tracheo-bronchial smooth muscle to a variety of stimuli ,
resulting in narrowing of air tubes and accompanied by
increased secretion , mucosal edema and mucus plugging.
• Characters :
– Clinical : (recurrent bouts of coughing, shortness of breath,
chest tightness, and wheezing)
– Physiological : (widespread, reversible narrowing of the
bronchial airways and a marked increase in bronchial
responsiveness to inhaled stimuli)
– Pathological : (lymphocytic, eosinophilic inflammation of the
bronchial mucosa, remodeling of the bronchial mucosa, with
deposition of collagen , hyperplasia of the cells of all structural
elements )

3. • Sub types of asthma
– Allergenic
– Non allergenic
– Extrinsic asthma : mostly episodic , less prone to status
asthmaticus
– Intrinsic asthma : perennial , status asthmaticus common
• Trigger factors : infection, irritants , pollution , exercise
, exposure to cold air , psychogenic)
• COPD- progressive disease with emphysema and
bronchial fibrosis in variable proprtions – mostly
caused due to smoking but may be aggravated by the
trigger factors .

4. Classification of drugs used in asthma
1)
BRONCHODILATORS :
i) sympathomimetics :
a) selective β2 agonists : ( salbutamol ,
terbutaline )
b) non selective β agonists : isoprenaline
c) non selective adrenergic agonists :
( adrenaline , ephedrine )
Short acting : albuterol , levalbuterol, metaproterenol, terbutaline
, and pirbuterol
long acting : salmeterol, formoterol
ii) methyl – xanthine derivatives : ( aminophylline , theophylline
iii) anti cholinergics : atropine , ipratropium

6. 2) Leukotriene antagonists : zafirleukast,
monteleukast, zileuton
3) Mast cell stabilizers : sodium cromoglycate ,
nedocromil , ketotifen
4) Corticosteroids :
i) systemic : hydrocortisone , prednisolone
ii) inhalational : beclomethasone , budesonide ,
fluticasone , flunisolide
5) Anti Ig-E monoclonal antibodies : omalizumab

7. Sympathomimetics : salbutamol
• Used for acute management , best reliever
• Stimulates adenylyl cyclase and increase the
formation of intracellular cAMP
• relaxes airway smooth muscle and inhibits
release of bronchoconstricting mediators from
mast cells. They may also inhibit microvascular
leakage and increase mucociliary transport by
increasing ciliary activity.
• Available as metered dose inhalers ,
• Bronchodilation maximal within 15–30 minutes
and persists for 3–4 hours

8. • Indications :
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Bronchospasm and bronchial asthma
Chronic bronchitis
Emphysema
Threatened abortion ( relaxes uterus )
Adverse effects :
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Nervousness
Drowsiness
Weakness
Tachycardia
Headache
Tremor
Dizziness

9. • Contraindications :
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Hyperthyroidism
Cardiac arrhythmia
Diabetes mellitus
Hypertension
Ischaemic heart disease,
Antepartum haemorrhage
Toxaemia of pregnancy
Hypersensitivity
Dose :
oral :2-4 mg
Im/sc: 0.25-0.5 mg
Inhalation :- 100-200 mcg in puffs

10. ADRENALINE(EPINEPHRINE)
Adrenaline is produced in the body by the cells of adrenal medulla and
chromaffin tissue.
Epinephrine is destroyed by the stomach acid and is therefore not
effective if taken orally.It is usually given by subcutaneous or IM
injection.
USES
• Bronchial asthma
• To provide rapid relief of acute allergic reactions to drugs and other
allergens,anaphylactic reactions
• Adrenaline is given along with local anaesthetics to prolong the
actions of anaesthetics
• Topical haemostatic to stop haemorrhage
• Wide angle glaucoma
• Cardiac resustication

11. ADVERSE EFFECTS
• Fear
• Anxiety
• Restlessness
• Headache
• Tremors
• Palpitation
• Tissue necrosis
• Large doses cause sharp rise in BP leading to
cerebral haemorrhage.

12. PRECAUTIONS
Adrenaline can cause sudden death in hypoxic subjects
Cause serious toxicity in patients receiving tricyclic antidepressants like imipramine
CONTRAINDICATIONS
Hypertension
Hyperthyroidism
Ischemic heart disease
DOSES
0.5ml of a 1:1000 solution IM
(this dose of drug should not be injected in vein by mistake as a sudden IV injection
can precipitate a fatal cardiac arrhythmia.
IV bolus in a dose of 1mg (10ml of a 1:10000 solution) as a stimulant to the heart in
cardiac arrest.

13. Methyl xanthines
• Aminophylline is a soluble physical complex of
theophylline and ethylenediamine.
• Mechanism :
– Blocks bronchoconstrictor action of adenosine by
competitive inhibition of purinergic receptors in
bronchus
– Inhibits enzyme phosphodiesterase ( PDE ) and
prevents degradation of cAMP and cGMP
– Translocates Ca ++ and makes it unavailable for
degradation of mast cells

14. • Pharmacological actions :
1) Lungs : bronchodilation
2) CNS : CNS stimulation , nervousness, anxiety ,
tremor , anxiety , insomnia , stimulates
respiratory centres
3) CVS : cardiac acceleration . Positive inotropic and
chronotropic action , vasodilation
4) Kidney : weak diuresis

15. • Indications :
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Severe bronchial asthma
COPD
Apnoea in pre term baby
Ordinary headache ( caffeine + aspirin)
Migraine
• Contraindications
– Cardiac or liver failure
– Peptic ulcer
– Pregnancy

16. • Adverse effects
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Tachycardia
Palpitations
Nausea
Cardiac arrhythmia
Nervousness
Convulsions ( rapid iv )
• Overdosage causes :
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Cardiac arrhythmia
Hypotension
Hypokalemia
Seizures
Severe vomiting
Treatment :
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Gastric lavage
Activated charcoal
K replacement
Diazepam

17. Anti cholinergic drug : atropine
• Cause bronchodilation by blocking cholinergic
constrictor tone
• Act primarily in larger air ways

18. Leukotriene antagonists
leukotriene are substances produced by inflammatory white cells ,which
cause spasm of the bronchial muscle .
Drugs are becoming available which prevent spasm either by blocking
the action of leukotrines or by preventing inflammation .They also
diminish hyperactivity of the bronchial mucosa and reduce inflammation.
MONTELUKAST AND ZAFIRLUKAST
These drugs antagonize cystenyl LT1 receptor mediated bronchoconstriction
,increased vascular permeability and eosinophil recruitment.
Well absorbed orally , highly plasma protein bound and metabolized by
Cytochrome P450 group of enzymes
ZILEUTON:
5-LOX inhibitor

19. INDICATIONS
Mild to moderate asthma
Preventing exercised induced asthma
Aspirin induced asthma
ADVERSE EFFECTS
Headache
Eosinophilia
Rashes
Neuropathy
Churg – strauss syndrome ( vasculitis with eosinophilia)

20. Corticosteroids
Exact mechanism of action of corticosteroids is not fully understood .these
drugs do not relax airway smooth muscle directly.However they produce
marked increase in airway caliber through following mechanism
1.Corticosteroids probably have a nonspecific anti-inflammatory activity which
reduces mucosal oedema and the viscous sputum.
2.corticosteroids modify immune response and stabilize mast cells
3.corticosteroids restore responsiveness of β2 adrenergic receptors to agonists
which may be impaired in some asthmatics.
USES
• Used to treat mild to moderate asthma
• Used to treat asthma that do not improve adequately with
bronchodilators or that worsens despite maintenance of bronchodilator
therapy
• Used in status asthmatic patients when he becomes refractory or asthma
stand in way of his life

21. ADVERSE EFFECTS
• Fluid retension
• Increased red cell mass
• Wt.gain
• Peptic ulcer
• Oropharyngeal thrush
• Hoarseness and weakness of voice
DOSE
• Hydrocortisone—inj IV:200mg repeated 4hrly
• Prednisolone—tab(5mg):30-60mg/day
• Beclomethasone---inhalation:100microgram,3-4times daily,2puffs 4 times
per day
• Betamethasone---inhalation 200microgram 3-4 times daily

22. Mast cell stabilisers
SODIUM CROMOGLYCATE
It is an effective drug against both early and late phase of bronchial asthma ,when given
prophylactically.children seems to respond to it better than adults.however it should be tried in all
patients whose asthma is poorly controlled with bronchodilators.
MECHANISM OF ACTION
1.It acts by inhibiting degranulation of sensitized mast cells .
chromoglycin sodium
↓
reduce accumulation of intracellular Ca ion induced by antigen in sensitized mast cells
↓
inhibit degranulation of mast cells
↓
no release of histamines,5HT
↓
prevents bronchoconstriction(prophylaxis)

23. USES
• Prophylaxis of
• -exercise:induced bronchoconstriction
• -aspirin:induced bronchoconstriction
• -bronchospasm:induced by industrial agents for eg wood dust
• Extrinsic (allergic) asthma in young patients
• Intrinsic asthma in old patients
• Allergic rhinitis
• To prevent seasonal increase in bronchial reactivity in patients with alleric asthma
ADVERSE EFFECTS
• It is a very safe drug .Its adverse effects are rare .However dry powder inhaler may
cause
• -throat irritation
• -coughing
• -occassionally wheezing
DOSE
20mg 4 times daily(4 inhalation daily)

24. Choice of treatment
1)
2)
3)
4)
5)
6)
Mild episodic asthma ( symptoms less than once daily): inhaled short
acting beta-2 agonist
Seasonal asthma : sod cromoglycate or low dose inhaled steroid ( 200400mcg/day) 3-4 weeks before anticipated attack
Mild chronic asthma with occasional exacerbations : symptoms once
daily – regular inhaled low dose steroid or inhaled cromoglycate
Moderate asthma with frequent exacerbations ( attacks affecting
activity and occuring more than once daily) : increased dose of inhaled
steroid ( upto 1600 mcg/day)
Severe asthma : ( continuous symptoms / frequent exacerbations / need
hospitalisation) : regular inhaled steroid ( 800-2000 mcg/day + inhaled
long acting beta-2 agonist twice daily)
Status asthmaticus /refractory asthma :
i)
ii)
iii)
iv)
v)
vi)
Hydrocortisone 100 mg iv stat followed by 100mg/8hr infusion
Nebulised salbutamol + ipratropium intermittent inhalations
Intermittent humidified oxygen inhalation
Salbutamol/ terbutaline 0.4 mg im/sc may be added
Chest infection to be treated with antibiotics
Dehydration and acidosis to be treated