Pharmacotharepy of cough

1. Pharmacotherapy of Cough
By
Dr. Manoj Kumar
Assistant Professor
Department of Pharmacology
Adesh Medical College & Hospital Ambala Can’t

2.  Cough is a useful protective reflex
that clears the respiratory tract of the
accumulated mucus and foreign substances.
 It occurs due to stimulation of mechano / chemo
receptors in throat, respiratory passage or stretch
receptors in the lung.

4. Most common causes of cough
• Common cold
• Upper/lower respiratory tract infection
• Allergic rhinitis
• Smoking
• Chronic bronchitis
• Pulmonary tuberculosis
• Asthma
• Gastroesophageal reflux
• Pneumonia
• Congestive heart failure
• Bronchiectasis
• Use of drugs (e.g. ACEI), glucocorticoids, iodine

5. COUGH
Non Productive (Dry)
Types of cough
Cough is 2 types
Productive (Tenacious)

6. Non productive:-
• No useful purpose.
• It increased discomfort to the patient.
• Treatment Antitussive agents are useful.
Productive cough:-
• It is characterized by presence of excessive sputum
and may be associated with conditions such as
chronic bronchitis and bronchiectasis.
• In this condition expectorants are useful.

7. • Antitussive
suppress the frequency as well as intensity of
coughing without affecting the normal elimination
of excessive secretions from the respiratory
tract.
• Expectorants
Increase the volume and decrease the viscosity
of secretions to enhance the force of the
secretion upward and outward by ciliary
movement and coughing.

8. Peripherally acting Centrally acting
Peripherally & centrally
Pharyngeal
demulcents
Expectorants
Opioids Non Opioids
Mucokinetics Mucolytic
Benzonatate
Classification of drugs

9. Peripherally acting
Pharyngeal demulcents
Lozenges
Cough drops
Linctuses containing syrup
Glycerine
Liquorice
Expectorants:-
1.Mucokinetics
– Ammonium chloride
– Sodium citrate
– Potassium Iodide
– Guaifenesin
– Ipecacuanha
2.Mucolytic
– Vasaka
– Bromhexine
– Ambroxal
– Dornase alfa
– Acetyl cysteine

10. Centrally and peripherally acting
• Opioids
Centrally acting
• Non Opioids
– Codeine
– Pholcodeine
– Morphine
– Ethylmorphine
– Noscapine
– Dexomethorphan
– Pipazethate
– Chlophedinol
– Oxeladin
• Benzonatate

11. Introduction to Cough
Types of cough
Classified based on duration, characters, quality and timing
Acute: Sudden onset/less than 3 weeks
Sub-acute: 3-8 weeks
Chronic: Longer than eight weeks

12. Drugs for cough
Cough can be treated :
By Nonspecific therapy
With specific remedies(antibiotics,etc)

13. Demulcents and expectorants
Pharyngeal demulcents
 Coat the pharynx and produce Sooth effect in throat.
 Increase flow of saliva from P. mucosa.
 Reduce afferent impulses from the
inflamed/irritated Mucosa
 Action less then – 30 mints.
 Useful for the symptomatic relief in
dry cough arising from throat

14. Expectorant
Two category:
Bronchial secretion enhancer
Mukolytics
Demulcents and expectorants cont…

15. Expectorants
Mucokinetics
• Bromhexine derivative of alkaloid vasicine obtained from
Adhatoda vasica.
• Potent mucolytic and mucokinetic, capable of inducing thin
copious bronchial secretion.
• It is particularly useful if mucus plugs are present.
• Side effects:- rhinorrhoea and lacrimation, nausea, gastric
irritation, hypersensitivity.
• Dose:- adults 8 mg TDS, children 1–5 years 4 mg BD,

16. Expectorants cont…
Ambroxol:
A metabolite of bromhexine
Mucolytic action, uses and side effects similar to bromhexine
Dose: 15-30 mg TDS
Acetylcysteine
Derivative of cysteine
Opens disulfide bonds on mucoproteins present in sputum
Also act as antioxidants
Reduce airway inflammation

17. Expectorants cont…
Carbocysteine:
Liquefies viscid sputum
Administered orally (250-750 mg TDS)
May be break gastric mucosal barrier
Contraindicated in peptic ulcer
Side effects: Gastric discomfort and skin rashes

18. Demulcents and expectorants cont…
Bronchial secretion enhancer
Sodium or Potassium citrate
 saltaction
Potassium iodide
 Secreted by bronchial glands
 Irritate airways mucosa
 Prolonged use
 Disturb thyroid function
 Iodism
 Not used now

19. Demulcents and expectorants cont…
Bronchial secretion enhancer
Guaiphenesin, Balsum of Tolu, Vasaka
Plant products
Enhance bronchial secretion
Promotes Mucocilliary function secreted
by tracheobronchial glands
Ammonium chloride
Ammonium salts
Increase respiratory secretions

20. Antitussives
Acts on CNS
Raise threshold of cough center
Act peripherally in respiratory tract
Reduce tussal response or both the action
Aimed to control the cough rather than eliminate
Used only for dry, unproductive cough or if cough is disturbs sleep
/hazardous

21. Antitussives (cont..)
Ophoids:
Codeine
 Opium alkaloid Less potent than morphine
 more selective for cough center
 Standard antitussive: suppress cough for 6 hours
Side effects:
 At higher doses respiratory depression especially in children
 Constipation is main drawback,
 Driving may be impaired
 Contraindicated in asthmatics and patients with diminished respiratory reserve
 Avoided in children.
 Abuse
Dose: 10–30 mg; children 2–6 years 2.5–5 mg, 6–12 years 5–10 mg

22. Antitussives (cont..)
Ophoids:
Ethylmorphine
Closely related to codeine
Has antitussive, respiratory depressant properties like codeine
Believed to be less constipating
Dose: 10-30 mg TDS
Pholcodeine
Similar in efficacy as antitussive to codeine
Long acting codeine (12h)
Dose: 10-15 mg.

23. Antitussives (contd..)
Nonopioids:
Noscapine
Opium alkaloid of benzoisoquinoline
Depresses cough but lacks narcotic, analgesic or
dependence inducing properties
Equipotent antitussive as codeine
Useful in spasmodic cough
Dose: 15-30 mg
Side effect:
Headache and nausea
Can produce bronchoconstriction by stimulating histamine release

24. Antitussives (cont..)
Nonopioids:
Dextromethorphan
A synthetic central NMDA receptor antagonist
d-isomer has antitussive action while l-isomer is analgesic.
Effective as codeine
Does not depress mucociliary function of the airway mucosa
Dose: 10–20 mg
Side effect:
Dizziness, nausea, drowsiness
At high doses hallucinations and ataxia may occur.

25. Antitussives (cont..)
Nonopioids:
Chlophedianol
A centrally acting antitussive
Slow onset and longer duration of action.
Dose: 20–40 mg
Side effect
Dryness of mouth
Vertigo
Irritability

26. Antitussives (cont..)
Peripherally acting antitussives:
Prenoxdiazine :
Desensitize the pulmonary stretch receptors and reduce tussal
impulses originating in the lungs
Indicated in cough of bronchial origin
Efficacy is not impressive
Dosage: 100-200 mgs TID-QID

27. Antitussives (cont..)
Antihistamines:
H1 blockers are added to antitussive/expectorants
 Relief in cough due to their sedative and
anticholinergic action
Lack selectivity for cough center
Have no expectorant property

28. Antitussives (cont..)
 Specially promoted for cough in respiratory allergic states
Commonly used antihistanines:
 Chlorpheniramine (2-5mg)
 Diphenhydramine (15-25mg )
 Promethazine (15-25mg)
 Second generation antihistamines like Terfenadine,
Loratadine are ineffective

29. Adjuvant Antitussives
Bronchodilators:
Bronchospasm can induce or aggravate cough
Pulmonary receptor stimulation can induce both cough and
bronchoconstriction in individual with bronchial hyperreactivity
Relieve cough and clear secretions by increasing surface velocity
of airflow during cough
Not used routinely

30. Specific treatment approach to cough
Etiology of cough
 Upper/lower respiratory tract infection
 Smoking/chronic
bronchitis/bronchiectasis
 Pulmonary tuberculosis
 Asthmatic cough
 Gastro esophageal reflux
 ACE inhibitor associated cough
 Postnasal drip due to sinusitis
Treatment approach
 Appropriate antibiotics
 Cessation of smoking/avoidance of pollutants,
steam inhalation
 Anti tubercular drugs
 Inhaled β2 agonists/corticosteroids/ipratropium
 Light dinner, diet modification, H2 blocker, PPI
 Losartan.
 Antibiotic, nasal decongestant, H1 antihistaminic

31. Wrong preacher for cough syrup
administration

32. Thank You