Drugs Acting on the Upper Respiratory Tract PDF

# Chapter 54: Drugs Acting on the Upper Respiratory Tract ## Drugs Used to Treat Upper Respiratory Infections #1 - Antitussives - Block the cough reflex - Decongestants - Decrease the blood flow to the upper respiratory tract and decrease the overproduction of secretions - Antihistamines...

# Chapter 54: Drugs Acting on the Upper Respiratory Tract ## Drugs Used to Treat Upper Respiratory Infections #1 - Antitussives - Block the cough reflex - Decongestants - Decrease the blood flow to the upper respiratory tract and decrease the overproduction of secretions - Antihistamines - Block the release or action of histamine that increases secretions and narrows airways ## Drugs Used to Treat Upper Respiratory Infections #2 - Expectorants - Increase productive cough to clear airways - Mucolytics - Increase or liquefy respiratory secretions to aid clearing of airways ## Sites of Action of Drugs Working on the Upper Respiratory Tract This image shows a diagram of the human body with labels showing where different types of drugs work on the upper respiratory tract. - **Medullary cough center:** Codeine, hydrocodone, dextromethorphan work here - **Mucolytics:** Work here - **Inhaled steroids:** Work here - **Mucus:** Benzonatate, guaifensin work here - **Antihistamines:** Work here - **Bronchodilators:** Work here - **Lung surfactants:** Work here - **Alveoli:** - **Topical nasal decongestants:** Work here - **Nasal steroids:** Work here ## Use of Upper Respiratory Tract Agents Across the Lifespan ### Children - Most agents have established pediatric guidelines. - Care must be taken because of adverse effects including sedation, confusion, and dizziness - Medications shouldn't be used for children under 2 years of age and should be used with extreme caution in children 2 to 6 years of age. - Educate parents about reading labels and following dosing guidelines. - Parents should be encouraged to implement nondrug measures to help the child cope. ### Adults - Adults may inadvertently overdose when taking multiple OTC preparations. - Adults can also be encouraged to use nondrug measures to help them cope. - The safety of these drugs during pregnancy and lactation has not been established. ### Older Adults - Older adults are more likely to develop adverse effects associated with drugs including sedation, confusion, and dizziness. - Older adults are also more likely to have renal and/or hepatic impairment. Doses should start at a lower level than recommended for younger adults, and the patient should be monitored closely. ## Antitussives #1 - Suppress the cough reflex: - Codeine (generic only) - Hydrocodone (available in some combination products) - Dextromethorphan (generic and in combination products) ## Antitussives #2 - **Actions**: - Act directly on the medullary cough center of the brain to depress the cough reflex - **Indications**: - Control nonproductive cough - **Pharmacokinetics**: - Rapidly absorbed, metabolized in the liver, and excreted in the urine ## Antitussives #3 - **Contraindications**: - Patients who need to cough to maintain the airway - Head injury or impaired CNS - **Caution**: - Hypersensitivity or history of narcotic addiction - **Adverse Effects**: - Drying effect on the mucous membranes - CNS adverse effects and GI upset - Drug-to-drug interactions- MAOI's ## Nursing Considerations for Antitussives - **Assess**: - History and Physical Exam and history of allergy - Temperature, respirations, adventitious sounds - Orientation and affect ## Prototype Antitussives: Dextromethorphan - **Indications**: Control of nonproductive cough - **Actions**: Depresses the cough center in the medulla to control cough spasms. - **Pharmacokinetics**: - **Route**: Oral - **Onset**: 25-30 minutes - **Peak**: 2 hours - **Duration**: 3-6 hours - **T 1/2**: 2 to 4 hours - **Metabolism**: Metabolized in the liver and excreted in urine - **Adverse Effects**: Dizziness, respiratory depression, dry mouth ## Topical Nasal Decongestants #1 - Decrease the overproduction of secretions by causing local vasoconstriction to the upper respiratory tract: - Oxymetazoline (Afrin, and others) - Phenylephrine (Coricidin, and many others) - Tetrahydrozoline (Tyzine) - Xylometazoline (Otrivin) ## Topical Nasal Decongestants #2 - **Actions**: - Sympathomimetic - Affects sympathetic nervous system to cause vasodilatation - Causing less inflammation of the nasal membrane - **Indications**: - Relieve the discomfort of nasal congestion that accompanies the common cold, sinusitis, and allergic rhinitis ## Topical Nasal Decongestants #3 - **Pharmacokinetics**: - Generally not absorbed systemically - Any portion of these topical decongestants that is absorbed is metabolized in the liver and excreted in the urine. - **Contraindications**: - Lesion or erosion in the mucous membranes - **Caution**: - Any condition that might be exacerbated by sympathetic activity ## Topical Nasal Decongestants #4 - **Adverse Effects**: - Local stinging and burning - Rebound congestion - Sympathomimetic effects - **Drug-to-Drug Interactions**: - Cyclopropane or halothane ## Nursing Considerations for Topical Nasal Decongestants - **Assess**: - History and Physical Exam and known allergy - Glaucoma, hypertension, diabetes, thyroid disease, coronary disease, and prostate problems - Orientation and reflexes, VS and cardiac status - Respirations and adventitious lung sounds - Nasal mucous membrane and urinary status - **Prototype**: Tetrahydrozoline ## Oral Decongestants #1 - Decrease nasal congestion related to the common cold, sinusitis, and allergic rhinitis - Pseudoephedrine (Triaminic Allergy Congestion, and many combination products) ## Oral Decongestants #2 - **Actions**: - Shrink the nasal mucous membrane by stimulating the alpha-adrenergic receptors in the nasal mucous membranes - **Indications**: - Promotion of drainage in the sinuses and improving air flow - **Pharmacokinetics**: - Well absorbed, widely distributed in the body - Metabolized in the liver and primarily excreted in urine ## Oral Decongestants #3 - **Contraindications**: - Any condition that might be exacerbated by sympathetic activity - **Adverse Effects**: - Rebound congestion - Sympathetic effects - **Drug-to-Drug Interactions**: - OTC products that contain pseudoephedrine; taking concurrently can cause serious side effects ## Nursing Considerations for Oral Decongestants - **Assess**: - History and Physical Exam and known allergy - Pregnancy, lactation, hypertension, CAD - Hyperthyroidism, diabetes mellitus, or prostate enlargement - Orientation, reflexes, and affect - VS and LS - **Prototype: **Pseudoephedrine ## Topical Nasal Steroid Decongestants #1 - **Actions**- relieve inflammation - Exact mechanism of action is not known - **Indications**: - Seasonal allergic rhinitis - Inflammation after the removal of nasal polyps - **Pharmacokinetics**: - Generally not absorbed systemically ## Topical Nasal Steroid Decongestants #2 - **Contraindications**: - Acute infection - **Caution**: - Active infection - Avoid exposure to airborne infections - **Adverse Effects**: - Local burning, irritation, stinging, dryness of the mucosa, and headache - Suppression of healing can occur in a patient who has had nasal surgery or trauma ## Nursing Considerations for Topical Nasal Steroid Decongestants - **Assess**: - History and Physical Exam and known allergy - Nasal mucosa, respiration and adventitious sounds - Temperature ## Prototype Topical Nasal Steroid Decongestants: Flunisolide - **Indications**: Treatment of seasonal allergic rhinitis for patients who are not getting any response from other decongestant preparations; relief of inflammation after the removal of nasal polyps. - **Actions**: Anti-inflammatory action, which results from the ability to produce a direct local effect that blocks many of the complex reactions responsible for the inflammatory response. - **Pharmacokinetics**: - **Route**: Topical (nasal spray) - **Onset**: Immediate - **Peak**: 10-30 minutes - **Duration**: 4-6 hours - **T 1/2**: Not generally absorbed systemically. - **Adverse Effects**: Local burning, irritation, stinging, dryness of the mucosa, headache, increased risk of infection ## Antihistamines #1 - Relieve respiratory symptoms and treat allergies - First-generation and second generation antihistamines include: - Brompheniramine (J-Tan) - Carbinoxamine (Histex, Palgic) - Chlorpheniramine(Aller-Chlor) and many others - See table 54.3 ## Antihistamines #2 - **Actions**: - Selectively block the effects of histamine at the histamine-1 receptor sites, decreasing the allergic response - Anticholinergic and antipruritic effects - **Indications**: - Seasonal and perennial allergic rhinitis, allergic conjunctivitis, uncomplicated urticaria, and angioedema - **Pharmacokinetics**: - Well absorbed, metabolized in the liver, excreted in urine and feces - **Contraindications**: - Pregnancy and lactation ## Antihistamines #3 - **Caution**: - Renal or hepatic impairment - History of arrhythmias - **Adverse Effects**: - Drowsiness and sedation - Anticholinergic effects - **Drug-to-Drug Interactions**: - Vary based on the drug ## Nursing Considerations for Antihistamines - **Assess**: - History and Physical Exam and known allergy - Pregnancy or lactation; and prolonged QT interval, renal or hepatic impairment - Skin, orientation, affect, and reflexes - Respirations and adventitious sounds - Appropriate lab values ## Prototype Antihistamines: Diphenhydramine - **Indications**: Symptomatic relief of perennial and seasonal rhinitis, vasomotor rhinitis, allergic conjunctivitis, urticaria, and angioedema; also used for treating motion sickness and parkinsonism and as a nighttime sleep aid and to suppress coughs. - **Actions**: Competitively blocks the effects of histamine at H1-receptor sites; has atropine-like antipruritic and sedative effects. - **Pharmacokinetics**: - **Route**: - Oral - IM - IV - **Onset**: - 15-30 minutes - 20-30 minutes - Rapid - **Peak**: - 1-4 hours - 1-4 hours - 30-60 minutes - **Duration**: - 4-7 hours - 4-8 hours - 4-8 hours - **T 1/2**: 2.5 to 7 hours; metabolized in the liver and excreted in urine. - **Adverse Effects**: Drowsiness, sedation, dizziness, epigastric distress, thickening of bronchial secretions, urinary frequency, rash, bradycardia. ## Expectorants #1 - Increase productive cough to clear the airways. They liquefy lower respiratory tract secretions, reducing the viscosity of these secretions and making it easier for the patient to cough them up - Guaifenesin (Mucinex, and many others). ## Expectorants #2 - **Actions**: - Enhances the output of respiratory tract fluids by reducing the adhesiveness and surface tension of these fluids, allowing easier movement of the less viscous secretions - **Indications**: - Symptomatic relief of respiratory conditions characterized by a dry, non-productive cough - **Pharmacokinetics**: - Rapidly absorbed; metabolism and excretion has not been reported ## Expectorants #3 - **Adverse Effects**: - GI symptoms - Headache - Dizziness - Mild rash - Prolonged use may result in masking a serious underlying disorder ## Nursing Considerations for Expectorants - **Assess**: - History and Physical Exam and known allergy - Persistent cough due to smoking, asthma, or emphysema - Skin, temperature, respirations and adventitious sounds, and orientation and affect ## Prototype Expectorants: Guaifenesin - **Indications**: Symptomatic relief of respiratory conditions characterized by dry, nonproductive cough and in the presence of mucus in the respiratory tract. - **Actions**: Enhances the output of respiratory tract fluid by reducing the adhesiveness and surface tension of the fluid, facilitating the removal of viscous mucus. - **Pharmacokinetics**: - **Route**: Oral - **Onset**: 30 minutes - **Peak**: Unknown - **Duration**: 4-6 hours - **T 1/2**: Unknown; metabolism and excretion are also unknown. - **Adverse Effects**: Nausea, vomiting, headache, dizziness, rash ## Mucolytics #1 - Increase or liquefy respiratory secretions to aid the clearing of the airways in high-risk respiratory patients who are coughing up thick, tenacious secretions - Acetylcysteine (generic) - Dornase alfa (Pulmozyme) ## Mucolytics #2 - **Actions**: - Work to break down mucous in order to aid the high-risk respiratory patient in coughing up thick, tenacious secretions - **Indications**: - Patients who have difficulty coughing up secretions - Patients who develop atelectasis - Patients undergoing diagnostic bronchoscopy - Postoperative patients - Patients with tracheostomies ## Mucolytics #3 - **Pharmacokinetics**: - Nebulization or direct instillation into the trachea - **Caution**: - Acute bronchospasm, peptic ulcer, and esophageal varicies - **Adverse Effects**: - GI upset - Stomatitis and/or rhinorrhea - Bronchospasm - Rash ## Nursing Considerations for Mucolytics - **Assess**: - History and Physical Exam and known allergy - Presence of acute bronchospasm, peptic ulcer and esophageal varices - Skin, B/P, pulse, respirations and adventitious sounds ## Prototype Mucolytics: Acetylcysteine - **Indications**: Mucolytic adjunctive therapy for abnormal, viscid, or inspissated mucous secretions in acute and chronic bronchopulmonary disorders; to lessen hepatic injury in cases of acetaminophen toxicity. - **Actions**: Splits links in the mucoproteins contained in the respiratory mucus secretions, decreasing the viscosity of the secretions; protects liver cells from acetaminophen effects. - **Pharmacokinetics**: - **Route**: - Instillation inhalation - Oral - **Onset**: - 1 minute - 30-60 minutes - **Peak**: - 5-10 minutes - 1-2 hours - **Duration**: - 2-3 hours - Unknown - **T 1/2**: 6.25 hours; metabolized in the liver and excreted in urine. - **Adverse Effects**: Nausea, stomatitis, urticaria, bronchospasm, rhinorrhea.