Anti asthmatic

							Anti asthmatic drugs

     Adit Muktadir
       Disorders of Respiratory Function

Classification
Main disorders of the respiratory system are :
  1. Bronchial asthma
  2. Cough
  3. Allergic rhinitis
  4. Chronic obstructive pulmonary disease
  (COPD, also called emphysema)
             Asthma

Asthma is a chronic inflammatory
 disorder of airways that result in
 airway obstruction in response to
          external stimuli
  Airways of the asthmatic patients are
  characterized by:
1. Inflammation
  • Swelling
  • Thick mucus production.
2. Bronchospasm
  • constriction of the muscles around the
    airways, causing the airways to become
    narrow.
Airway       hyper-reactivity:    abnormal
sensitivity of the airways to wide range of
external stimuli as pollen, cold air and
tobacco smoke.
            Symptoms of asthma
Asthma produces recurrent episodic attack of
 Acute bronchoconstriction (immediate)
 Shortness of breath
 Chest tightness
 Wheezing
 Rapid respiration
 Cough
Symptoms can happen each time the airways
   are irritated.
Causes
   Infection
   Emotional conditions
   Stress
   Exercise
   Pets
   Seasonal changes
   Some drugs as aspirin
            Classification
A) Drugs which act directly on the bronchial smooth
  muscles to relax it
   1. Sympathomimetics
      • Selective B2 agonist
          – Salbutamol
          – Trbutaline
      • B agonist
          – Isoprenaline
          – Orciprenaline
      • Alpha-Beta agonist
          – Adrenaline
          – Ephedrine
2. Methyl-xanthine derivatives
  –   Aminophyline
  –   Theophyline
  –   Enprophyline
  –   Caffeine
  –   Theobromine
  –   Proxifylline
 B. Drugs which non-specifically
reduce the response of antigen-
       antibody reaction

1. Adrenal steroids
     Dexamethasone
     Betamethasone
     Prednisolone
2. Di-sodium chromoglycate
C. Anti cholinergic drugs
• Iptropium Br
• Atropine
    D. Antihistamines
• Ketotifen
• Terfenamide
• Astemizole
         Salbutamol
• Selective beta-2 blockers
• Oral route is effective
      Pharmacokinetics
• ROA : inhalation, oral, I.V.
• have rapid onset of action (15-30 min), 5
  min by inhalation
• duration of action (3 – 4 hr)
• Dose 1-2 puffs, 4-8 hourly
                   MOA
• Salbutamol is a beta(2)-adrenergic agonist
  and thus it stimulates beta(2)-adrenergic
  receptors in the lungs. Thus results in
  relaxation of bronchial smooth muscles.
• It is believed that Salbutamol increases
  cAMP production by activating adenylate
  cyclase, and the actions of salbutamol are
  mediated by cAMP.
• Increased intracellular cyclic AMP
  increases the activity of cAMP-dependent
  protein kinase A, which inhibits the
  phosphorylation of myosin and lowers
  intracellular calcium concentrations.
• A lowered intracellular calcium
  concentration leads to a smooth muscle
  relaxation.
• Increased intracellular cyclic AMP
  concentrations also cause an inhibition of
  the release of mediators from mast cells in
  the airways
          Indication
• Bronchospasm and bronchial asthma
• Chronic bronchitis
• Emphysema ( Emphysema is a long-
  term, progressive disease of the
  lungs that primarily causes shortness
  of breath )
• Threatened abortion
        Adverse effects
•   Nervousness
•   Drowsiness
•   Weakness
•   Tachycardia
•   Headache
•   Tremor
•   Dizziness
      Contraindication
• Hyperthyroidism
• Ischemic heart disease
• Diabetes