Respiratory Drug Agents

1. Respiratory Drug Agents .

2. Introduction • These are drugs that we use respiratory infections including upper and lower respiratory infections.

3. Anti-histamines • Any substance capable of reducing the physiologic and pharmacological effects of histamine. • Histamine is a bodily substance that performs many functions.

4. Continue • CNS transmission • Dilation of capillaries • Contraction of smooth muscles • Stimulation of gastric secretion • Acceleration of the heart rate

5. Continue • There are two types of cellular receptors for histamine: • H1 receptor • H2 receptor

6. Continue • Antihistamines are drugs that directly compete with histamine for specific receptor , for this reason they call antagonists. • H2 antagonists include • Cimetidine • Ranitidine • Famotidine • Nizatidine

7. Continue • H1 antagonists include • Diphenhydramine • Chlorpheniramine • Terfenadine • Astemizole

8. Therapeutic Uses • They are greatest value in the treatment of nasal allergies. • They are used for palliative therapy of common colds • They are used to prevent nausea and vomiting, for motion sickness • They reduce nasal, salivary and lacrimal gland secretion. • Proved to be safe and effective as sleep aid.

9. Mechanism of actions • Work by inhibiting the action of histamine through out the body. • Prevent stimulation of chemo trigger receptor zone (CTZ).

10. Side Effects • Dry mouth • Drowsiness • Constipation • Impotence • Sedation • Nervousness • Restlessness • Difficulty in urinating

11. Astemizole • Has the longest half-life (20-60 hrs) • Dosed once a day • Has very poor ant cholinergic activity. • Indicated for the treatment of seasonal variation especially in allergy rhinitis. • Cautiously given with a patient who have liver problem. • Contraindicated patients with hypersensitivity.

12. Continue • It is classified pregnancy category C. • Available in 10mg. • Recommended 10mg/day, given as a single dose.

13. Loratidine (claritin) • It is a non-sedating antihistamine drug. • Used to relieve symptoms of seasonal allergies, hay fever. • Classified pregnancy category B agent. • Contraindicated in patient shown hypersensitivity. • Available in 10mg tablet. • Recommended once a day.

14. Terfenadine (seldane) • Terfenadine was the first non-sedating anti histamine to come available. • Has short half life • Used to relieve the symptoms of seosonal allergic rhinitis. • It is a pregnancy category C. • Available only for oral preparation.

15. Continue • Terfenadine it self comes 60mg tablet, the combination product contains 60mg of Terfenadine and 120mg of pseudoephedrine. • Usual recommended dosage is 60mg twice daily, BID.

16. Diphenhydramine (Benadryl) • Diphenhydramine is older and traditional anti-histamine. • Has potent of ant cholinergic effect. • Classified pregnancy category B agent. • Contraindicated for • Hypersensitivity • Nursing mother • Neonates

17. Continue • Available oral, parentral, and topical preparations. • 25mg-50mg cap oral • 12.5mg/5ml syrup • 10mg/ml- 50mg/ml injection • 1%-2% cream topically

18. Chlorpheniramine(priton) • Available as 4mg, 8mg, and 12mg tablets. • Available as POM or OTC • Recommended oral dosage is 4mg ever 4 hrs or 6 hrs, given with a full glass water. • It is a pregnancy category C.

19. Cyproheptidine • Available as 2mg/5ml syrup and 4mg tablets. • It is recommended 4mg in TID, QID. • It is a pregnancy category B.

20. Dimenhydrinate • It is a POM drug, available 50mg tablets. • Recommended oral adult dosage is 50mg-100mg every 4 to 6 hours. • Recommended in children for 25mg-50mg ever 6 or 8 hour. • Taken half an hour before the travel. • It is rated in pregnancy category B.

21. Triprolidine (actidil) • It is an OTC drug available as 1.25mg/5ml syrup and 2.5mg tablet. • The recommended adult dosage is 2.5mg every 4 to 6 hour, taken with a full of glass water. • It is rated in pregnancy category B.

22. Promethazine (phenergan) • It is a prescription drug available as 25 and 50mg/ml injection, as a 6.25 and 25mg/ml syrup. • The recommended adult dosage is 12.5mg and 25mg TID. • It is rated pregnancy category C.

23. Clemastine (tavist) • It is a prescription drug available as 0.67mg/5ml syrup and 1.34mg, 2.68 mg tablets. • The recommended oral adult dosage is 1.34mg and 2.68mg TID. • It is rated in pregnancy category B agent.

24. Anti-tissuves • Coughing is a normal physiologic function and serves the purpose of removing potentially harmful foreign substance and excessive secretions from the respiratory tract. • The cough reflex is stimulated when receptors in bronchi, alveoli, and pleura are stretched.

25. Etiology of cough • Upper or lower respiratory tract infections. E.g appropriate antibiotics • Smoking. E.g cessation of smoking • Pulmonary tuberculosis. E.g antitubercular drugs. • Asthmatic cough. E.g inhaled beta2 agonist/corticosteroids. • Rhinitis. E.g avoidance in precipitating factor, corticosteroids or H1 blockers.

26. Continue 6. Gastroesophageal reflux. E.g H2 blockers, PPI. 7. ACE inhibitor associated cough. E.g losartan, calcium channel blockers.

27. Drugs for cough • Pharyngeal demulcents • Lozenges • Cough drops • Glycerine • Linctuses containing syrup 2. Expectorants • Sodium or potassium citrate • Potassium iodide • Guiphenesin • Ammonium chloride

28. Continue 3. Antitussives • Codeine • Pholcodeine • Noscapine • Dextrometrophan • Chlophedianol • Chlorpheniramine • Diphenhydramine • Promethazine

29. Continue 4. Adjuvant antitussives • Salbutamol • Terbutalin

30. Conntinue • This causes a signal to be sent to the cough center in the medulla of the brain, which in turn stimulates the cough. • Cough can be classified into: • Productive cough • Non-productive cough

31. Continue • There are two main categories of these agents: • Narcotic agents • Non-narcotic agents

32. Narcotic Agents • Narcotic agents have anti-tissuve effects. • They are effective in suppressing the cough reflex. • They are POM drugs. • Their use lead dependence • Codeine • Hydrocodeine

33. Non-narcotic • Non-narcotic antitissuve drugs are less effective than the narcotic ones. • They are available either alone or combination with other agents, they are POM drugs. • Dextromethorphan • Benzonatate

34. Mechanism of Actions • The narcotic anti-tissuves codeine and Hydrocodeine suppress the cough reflex through a direct action on this cough center. • Non-narcotic drugs suppress the cough reflex by anesthetizing (numbing) and thus keeping the cough reflex from being stimulated in the medulla.

35. Therapeutic Uses • Anti-tissuves are primarily used to stop the cough reflex, when the cough is non-reproductive and harmful

36. Side-Effects • Dizziness • Headache • Drowsiness • Dry mouth • Nausea • Vomiting • Constipation

37. Dextromethorphan • Dextromethorphan is a non narcotic anti tissuve drug. • It is widely used because of safety, non-addicting and does not cause respiratory depression. • It is a pregnancy category C. • Adult dose is 10-30mg q4h-q8h • It is contraindicated, hypersensitivity, headache and asthma.

38. Benzonatate (Tessalon) • It is a non narcotic anti-tissuve drug. • Anesthetizing or numbs the cough receptor. • Available only in a POM. • It is a pregnancy category C • Adult dose is 100mg TID.

39. Codeine • It is a very popular narcotic anti-tissuve drug. • It is a potentially addictive. • Depress respirations and the CNS activity. • It is classified pregnancy category C. • Adult dose is 10-20mg q4h-q6h. • It is contraindicated: • Hypersensitivity • Respiratory depression • Seizure disorders

40. Somaliland Anti-tissuves • Flucor day • Paracetamol 250mg • Pseudoephedrine 30mg • Dextromethorphan • Kuf-Go • Aminophylline • Diphenhydramine • Ammonium chloride

41. Continue • Bronchophane • Guaiphenesin 50mg • Ephedrine HCL 7.5mg • Diphenhydramine HCL 5mg • Dextromethorphan 4.58mg

42. Continue • Tussilar • Chlorpeniramine maleate 0.080 g • Dextromethorphan 0.125g • Ephedrine HCL 0.150g • Guaiphenesin 1g

43. Bronchodilators • These are drugs that are used for the lower respiratory tract infections (LRTI): • Asthma • Emphysema • Chronic bronchitis • Chronic obstruction pulmonary disease (COPD).

44. Continue • Bronchodilators can be classified into based on their mechanism of actions: • Beta-agonists • Xanthine derivatives • Corticosteroids

45. Beta-agonists • Beta-agonists are large group of drugs that are commonly used during the acute phase of an asthmatic attack. • They are agonists or stimulators of the sympathetic nervous system.

46. Continue • There are three types of beta-agonist bronchodilators: 1. Non-selective adrenergic drugs, which stimulate the alpha, beta one (cardiac), and beta two (respiratory) receptors. E.G, epinephrine 2. Non- selective beta adrenergic drugs, which stimulate both beta one and beta two receptors. E.g isoproterenol

47. Continue 3. Selective beta two drugs, which only stimulate the beta two receptors. E.g Albuterol (Salbutamol)

48. Mechanism of Action • Bronchodilators begins at the speacific receptors. • stimulating receptors, dilate the airways.

49. Albuterol (Salbutamol) • It is a commonly used drug in acute asthma attacks. • Used for prevention of acute attacks • It is a pregnancy category C drug. • It is a prescription drug • Available 2-4mg tablet, 2mg/5ml syrup, 0.083% solution and 0.5 % concentration solution.

50. Continue • Pediatric dose is 0.1mg/kg TID or 2mg Tid or Qid. • Adult dose is 2 inhalational q4h-q6h. • Available in the forms of: • Aerosol • Solution • Powder