COUGH dry and productive cough treatment ppt.pptx

drugs for productive and dry cough

1. COUGH Dr.S.Santhosh Post - Graduate

2. Cough is defined as the forced expiration of the contents of the respiratory tract. It is a protective reflex and helps to expel irritant matter from the respiratory tract.

3. PHYSIOLOGY Stimulation of the mucosal and C – fibre receptors in pharynx, larynx, trachea or bronchi generates tussal impulses. These are carried by the afferent fibres in the vagus and sympathetic nerves to the brainstem nucleus solitarius, which is connected to the central cough generator – Medullary cough centre which initiates the act of coughing.

4. TYPES Productive associated with production of large quantity of sputum. Non – productive dry cough

5. ETIOLOGY Environmental pollutants Smoking Common cold Chronic sinusitis Allergic rhinitis Upper respiratory tract infections Acute lung infections Chronic pulmonary diseases

6. DRUGS FOR COUGH - CLASSIFICATION Pharyngeal demulcents: syrups and linctuses Mucoactive drugs: expectorants, mucolytics, mucokinetics Central cough suppressants: Opioids – Codeine, Dextromethorphan, Pholcodeine Non – opioids – Caramiphene , Pipezethate Peripherally acting compounds: Local anaesthetics – Benzonatate, nebulized Lignocaine

7. PHARYNGEAL DEMULCENTS Act by increasing the flow of saliva – provide soothing effect. Useful in cough due to irritation of the pharyngeal mucosa above the larynx. Available in the form of Lozenges, Cough drops, etc.,

8. MUCOACTIVE DRUGS They alter the viscoelastic properties of the mucus and also promote clearance of the secretions.

9. EXPECTORANTS Increase the production of the demulcent respiratory tract fluid that protects and covers the irritated respiratory mucosa. They may act directly or indirectly as irritants to gastric vagal receptors to stimulate glandular exocytosis of a less viscous mucous. Eg : Hypertonic saline, Guaifenesin Aqueous extract of vasaca also produces same effect.

10. MUCOLYTICS Make the sputum less viscid so that it can be easily expectorated.

11. N - ACETYLCYSTEINE Acts by hydrolysing the disulfide bonds that link the mucin monomers and depolymerizes the mucin glycoprotein oligomers. Also has anti – oxidant and anti – inflammatory properties. 2ml 10% solution is given through nebulization 8 th hourly for 5 – 10 days Adverse effects: bronchospasm, fever, nausea, vomiting, stomatitis, rhinorrhea and haemoptysis .

12. DORNASE ALPHA It is a recombinant human deoxyribonuclease peptide mucolytic. Acts by breaking down the highly polymerized DNA released by degenerating neutrophils in purulent sputum.

13. BROMHEXINE It is an alkaloid from Vasaca plant. MOA: It depolymerises mucopolysaccharides of mucus directly and also increases lysosomal activity that breaks fibre network of tenacious sputum. Dose:8 – 16mg TDS Side effects: rhinorrhea, GIT upset. AMBROXOL is a metabolite of Bromhexine and has similar mechanism of action.

14. MUCOKINETICS Mechanism of action: These drugs stimulate the flow of respiratory secretions by stimulating the bronchial secretory cells and the ciliary movement. Examples: Essential oils: mild expectoration by bronchial secretory cell stimulation. Sodium citrate: gets converted to bicarbonates and helps mucous become less viscous.

15. Guaiacol, Guaifenesin: safe expectorants with proven efficacy. Dose: 100 – 200mg BD or TDS

16. ANTI - TUSSIVES Mechanism of action: They possess central anti – tussive actions by virtue of suppressing the cough center that mediates the cough reflex.

17. CENTRALLY ACTING ANTITUSSIVES Codeine: semisynthetic opioid analgesic; lesser addiction liability and less constipating; overdose – respiratory depression, convulsion, postural hypotension, tachycardia. (10mg BD or TDS) Pholcodeine : More potent and longer acting (10 – 15mg BD) Dextromethorphan: minimal drowsiness, less constipating; as potent as Codeine. (10mg TDS) Noscapine: opium alkaloid; no analgesic activity, drowsiness and addiction liability. (40mg TDS) Pipazethate : Phenothiazine group of antitussive (40mg TDS)

18. PERIPHERALLY ACTING ANTI - TUSSIVES Prenoxdiazine: inhibits pulmonary stretch receptors; moderate antitussive action (100 -200mg TDS) Local anaesthetics : Xylocaine and bupivacaine can be applied to pharynx and larynx to reduce sensitivity of sensory receptors for cough in this area.

19. Benzonatate: has both central and peripheral antitussive action. Actions: 1)inhibition of afferent cough impulses 2)inhibition of pulmonary stretch receptors. Side effects: drowsiness, headache, nausea, vertigo. Dose: 100 -200 mg TDS

20. ANTITUSSIVE – Contraindications: asthma chronic bronchitis bronchiectasis