1. Introduction to Clinical Pharmacology Chapter 31 Upper Respiratory System Drugs

2. Common Conditions of the Upper Respiratory System
Infections
Allergic rhinitis
Coughs
Common cold
Congestion

3. Medication Classes
Intranasal steroids or antihistamines relieve allergy symptoms
Promethazine and diphenhydramine are used to treat motion sickness also
Decongestants reduce nasal edema
Such as phenylephrine and oxymetazoline
Antitussives, mucolytics, and expectorants treat accompanying cough 

4. Antihistamines: Actions
Antihistamines block most, but not all, of the effects of histamine
First-generation antihistamines bind nonselectively to central and peripheral H1 receptors and may result in CNS stimulation or depression
Other first-generation drugs may have additional effects: antipruritic (anti-itching) or antiemetic (antinausea) effects
Second-generation antihistamines are selective for peripheral H1 receptors and, as a group, are less sedating

5. Antihistamines: Uses #1
Seasonal and perennial allergies
Allergic and vasomotor rhinitis
Allergic conjunctivitis
Mild and uncomplicated angioneurotic edema and urticaria
Allergic reactions to drugs, blood, or plasma
Coughs caused by colds or allergy

6. Antihistamines: Uses #2
Adjunctive therapy in anaphylactic shock
Treatment of parkinsonism
Relief of nausea and vomiting
Relief of motion sickness
Sedation
Adjuncts to analgesics

7. Antihistamines: Adverse Reactions
Central nervous system reactions
Drowsiness or sedation; disturbed coordination
Anticholinergic effects (cholinergic blocking)
Dryness of mouth, nose, and throat; thickening of bronchial secretions

8. Antihistamines: Contraindications and Precautions #1
Contraindicated during pregnancy and lactation
First-generation antihistamines: patients with known hypersensitivity to the drugs, newborns, premature infants, nursing mothers, individuals undergoing monoamine oxidase therapy, and in patients with angle- closure glaucoma, stenosing peptic ulcer, symptomatic prostatic hypertrophy, and bladder neck obstruction

9. Antihistamines: Contraindications and Precautions #2
Second-generation antihistamines: patients with known hypersensitivity
Cetirizine is contraindicated in patients who are hypersensitive to hydroxyzine
Used with caution in patients with bronchial asthma, cardiovascular disease, narrow-angle glaucoma, symptomatic prostatic hypertrophy, hypertension, impaired kidney function, peptic ulcer, urinary retention, pyloroduodenal obstruction, and hyperthyroidism

10. Antihistamines: Interactions
Interactant drug
Effect of Interaction
Rifampin
May reduce the absorption of antihistamine, fexofenadine, for example
Monamine oxidase inhibitors
Increase in anticholinergic and sedative effects of antihistamine
CNS depressants
Possible additive CNS depressant effect
Beta blockers
Risk for increased cardiovascular effects, with diphenhydramine, for example
Aluminum- or magnesium-based antacids
Decreased concentrations of antihistamine in blood, fexofenadine, for example

11. Decongestants: Actions and Uses
Nasal decongestants: sympathomimetic drugs, which produce localized vasoconstriction of the small blood vessels of the nasal membranes
Uses:
Used to treat the congestion associated with the following conditions:
Common cold; hay fever; sinusitis; allergic rhinitis; congestion associated with rhinitis

12. Decongestants: Adverse Reactions and Contraindications
Use of oral decongestants may result in the following adverse reactions:
Tachycardia and other cardiac arrhythmias; nervousness; restlessness; insomnia; blurred vision; nausea; vomiting
Contradicted:
In patients with known hypersensitivity and patients taking monoamine oxidase inhibitors
Sustained-released pseudoephedrine is contraindicated in children younger than 12 years of age

13. Decongestants: Precautions
Decongestants are used cautiously in patients with:
Thyroid disease; diabetes mellitus; cardiovascular disease; prostatic hypertrophy; coronary artery disease; peripheral vascular disease; hypertension; glaucoma
Pregnant women should consult with their primary health care provider before using these drugs

14. Decongestants: Interactions
Interactant drug
Effect of interaction
MAOIs
Severe headache, hypertension, and possibly hypertensive crisis
Beta-adrenergic blocking drugs
Initial hypertension episode followed by bradycardia

15. Antitussives, Expectorants, and Mucolytics: Actions and Uses
Expectorants increase the production of respiratory secretions, which in turn appears to decrease the viscosity of the mucus. This helps to raise secretions from the respiratory passages
Antitussives are used to relieve a nonproductive cough
depress the cough center located in the medulla and are called centrally acting drugs
Benzonatate (Tessalon) and potassium iodide are exceptions; they work peripherally by anesthetizing stretch receptors in the respiratory passages, thereby decreasing cough.
Expectorants are used to help bring up respiratory secretions

16. Antitussives, Expectorants, and Mucolytics: Adverse Reactions
Lightheadedness, Dizziness, Drowsiness or sedation
Coadministration of dextromethorphan (a nonopioid antitussive) and phenelzine (a monoamine oxidase inhibitor) may result in hypotension, fever, nausea, leg jerking, and coma.
Codeine-containing antitussives should be used cautiously during pregnancy and labor and in clients with COPD, acute asthma attacks, pre-existing respiratory disorders, acute abdominal conditions, head injury, increased intracranial pressure, convulsive disorders, hepatic or renal impairment, and prostatic hypertrophy.
Contraindicated in history of premature infants
Eucalyptus is used as a decongestant and expectorant and is found as a component in OTC products used for the treatment of sinusitis and pharyngitis. Contraindicated during pregnancy and lactation, people hypersensitive to eucalyptus and in children younger than 2 years of age

17. Nursing Process: Assessment #1
Preadministration assessment:
The assessments the nurse may perform:
Assess the involved areas (eyes, nose, and upper and lower respiratory tract) if the patient is receiving an antihistamine for the relief of allergy symptoms
If promethazine (Phenergan) is used with an opioid to enhance the effects and reduce the dosage of the opioid, take the patient’s blood pressure, pulse, and respiratory rate before giving the drug

18. Nursing Process: Assessment #2
Ongoing assessment:
Observe the patient for the expected effects of the antihistamine and for adverse reactions
Antihistamine is given for a serious situation: assess the patient at frequent intervals until the symptoms appear relieved and for about 24 hours after the incident

19. Nursing Process: Assessment #3
Preadministration assessment:
Assess the patient’s vital signs and congestion before administering the decongestants; assess the lung sounds and bronchial secretions to include color and amount of sputum, and note in the patient’s records; obtain the history of the use of the products to include home remedies may have tried
Ongoing assessment:
Assess the patient’s blood pressure, pulse, and congestion;include assessing lung sounds, frequency of cough, pain assessment; monitor client is has history of persistent cough; question the patient about attaining therapeutic effects and presence of adverse reactions

20. Nursing Process: Diagnoses
Risk for Injury related to drowsiness, dizziness, or sedation
Ineffective Airway Clearance related to pooling of or thick secretions
Impaired Oral Mucous Membranes related to dry mouth, nose, and throat

21. Nursing Process: Planning #1
The expected outcomes for the patient depend on the reason for administration of the antihistamine but may include:
Optimal response to therapy
Supporting of patient needs related to managing adverse reactions
Understanding of and compliance with the prescribed treatment regimen

22. Nursing Process: Planning #2
Expected outcomes for the patients include:
Optimal response to therapy
Support of patient needs related to the management of adverse reactions
Understanding of and compliance with the prescribed treatment regimen

23. Nursing Process: Implementation #1
Monitoring and managing patient needs:
Ineffective Airway Clearance
Encourage increase fluids
Assist with deep diaphragmatic breaths
Change positions often
Impaired oral mucous membranes:
Dryness of the mouth, nose, and throat: Offer the patient frequent sips of water or ice chips to relieve the symptoms
Risk of injury:
Assist the patient with ambulation
Place the call light within easy reach and instruct to call before attempting to get out of bed and ambulating

24. Nursing Process: Implementation #2
Loratadine or other rapidly disintegrating tablets can be administered with or without water and are placed on the tongue, where the tablet dissolves almost instantly.
Fexofenadine is not administered within 2 hours of an antacid.
Chewing benzonatate (Tessalon) tablets may result in a local anesthetic effect (oropharyngeal anesthesia) with possible choking as a result, therefore inform clients that they need to swallow whole.
Acetylcysteine has a distinctive, disagreeable odor. The medication may smell like “rotten eggs.” Although this odor may be nauseating, the smell dissipates quickly.

25. Nursing Process: Implementation #3
Promoting an optimal response to therapy
Ineffective breathing pattern:
Overuse of topical form: “Rebound” nasal congestion
Patient is taught to take the drug exactly as prescribed or discontinue the drug therapy gradually

26. Nursing Process: Implementation #4
Educating the patient and family:
Review the dosage regimen and possible adverse drug reactions with the patient

27. Nursing Process: Implementation #5
Educating the patient and family: The nurse should include the following points in the teaching plan:
Use this product as directed by the primary health care provider or on the container label
• Understand that overuse of topical nasal decongestants can make the symptoms worse, causing rebound congestion
If using a spray, do not allow the tip of the container to touch the nasal mucosa and do not share the container with anyone

28. Nursing Process: Implementation #5
Educating the patient and family: The nurse should include the following points in the teaching plan:
• Do not exceed the recommended dose.
• Avoid irritants, such as cigarette smoke, dust, or fumes, to decrease irritation to the throat.
• Drink plenty of fluids (if not contraindicated by disease process). A fluid intake of 1500 to 2000 mL is recommended.
• If taking oral capsules, do not chew or break open the capsules; swallow them whole.
• If taking a lozenge, avoid drinking fluids for 30 minutes after use to avoid losing effectiveness of the drug.
• Antihistamines may cause dryness of the mouth and throat. Frequent sips of water, sucking on hard candy, or chewing gum (preferably sugarless) may relieve this problem.
• High doses of antihistamines can contribute to mental changes in vulnerable populations.

29. Nursing Process: Implementation #5
Educating the patient and family: The nurse should include the following points in the teaching plan:
• Do not drive or perform other hazardous tasks if drowsiness occurs. This effect may diminish with continued use.
• Avoid the use of alcohol, as well as other drugs that cause sleepiness or drowsiness, while taking these drugs.
• Nasal burning and stinging may occur with the topical decongestants. This effect usually disappears with use.
• Use of INS can result in a fungal infection of the nares. Contact the primary health care provider if the area becomes reddened, sore, or you can see white patches.
• If the cough is not relieved or becomes worse, contact the primary health care provider.
• If chills, fever, chest pain, or sputum production occurs or changes color, contact the primary health care provider as soon as possible.

30. Nursing Process: Evaluation #1
Mucous membranes are moist and intact
No injury is reported
The patient and family understand the drug regimen

31. Nursing Process: Evaluation #2
The patient maintains effective breathing pattern
The therapeutic effect is achieved
The patient demonstrates an understanding of and compliance with the drug regimen