28 Drugs Used to Treat Respiratory Conditions

Figure 28-1A The upper respiratory tract.

Figure 28-1B The lower respiratory tract.

Figure 28-2 Bronchioles and alveoli.

Asthma Chronic disease caused by increased reactivity of the tracheobronchial tree to various stimuli Affects about 16 million Americans Classified according to cause: allergy, exercise-induced, or infections of respiratory tract

Figure 28-3 The effects of asthma on the bronchioles.

Isoproterenol Isoproterenol (Isuprel) is often used to treat asthma in children. However, this use is not a labeled indication for the drug. Advise parents and children that saliva and sputum may appear pink after inhalation—this is normal.

Table 28-1 The Most Common Antiasthma Drugs

Table 28-1 (continued) The Most Common Antiasthma Drugs

Table 28-1 (continued) The Most Common Antiasthma Drugs

Table 28-1 (continued) The Most Common Antiasthma Drugs

Table 28-1 (continued) The Most Common Antiasthma Drugs

Table 28-1 (continued) The Most Common Antiasthma Drugs

Table 28-1 (continued) The Most Common Antiasthma Drugs

Bronchodilators Agents that widen the diameter of bronchial tubes: Beta2-adrenergic agonists Xanthines

Beta2-Adrenergic Agonists: Uses Drugs of choice in acute bronchospasm; produce bronchodilation by relaxing smooth muscles of bronchial tree Used to relieve bronchospasm of asthma, to treat bronchitis and other obstructive airway diseases

Beta2-Adrenergic Agonists: Adverse Effects Restlessness Headache Dizziness Palpitations Insomnia Nausea and vomiting Anorexia Tachycardia

Beta2-Adrenergic Agonists: Contraindications Contraindicated in glaucoma, cardiogenic shock Safety during pregnancy and lactation not established

Beta2-Adrenergic Agonists: Contraindications Cautious use in older adults or debilitated patients; and in those with prostatic hypertrophy, hypertension, diabetes, hyperthyroidism, Parkinson’s disease, tuberculosis, and psychoneurosis

Beta2-Adrenergic Agonists: Patient Information Instruct patients to not exceed dosage. Advise patients to eat small, frequent meals to prevent nausea. Instruct patients to report chest pain, dizziness, insomnia, weakness, tremors, irregular heartbeat, difficulty breathing, productive cough, or lack of therapeutic effects.

Xanthines: Uses Drugs chemically related to caffeine that dilate bronchioles by relaxing smooth muscle Used for prophylaxis and symptomatic relief of bronchial asthma and bronchospasm associated with chronic bronchitis and emphysema

Xanthines: Adverse Effects Common: palpitations, tachycardia, flushing, hypotension, insomnia, nervousness, nausea and vomiting, diarrhea, tachypnea Serious: respiratory arrest

Xanthines: Contraindications Should not be given to patients with coronary artery disease, history of angina, or severe renal or liver impairments Safety during pregnancy and lactation not established

Xanthines: Contraindications Cautious use in children and older adults; those with hyperthyroidism, hypertension, peptic ulcer, prostatic hypertrophy, glaucoma, and diabetes

Xanthines: Patient Information Advise patients to take at same time each day. Instruct patients to avoid charbroiled food, limit caffeine intake, and avoid smoking. Women should not breast feed while taking these drugs.

Corticosteroids: Uses Mechanism of action believed to be diminished activation of inflammatory cells and increased production of anti-inflammatory mediators Used to treat respiratory conditions such as nasal congestion and allergic conditions such as rhinitis and asthma

Corticosteroids: Adverse Effects Irritation of mucous membranes Headache Pharyngitis Epistaxis Nausea and vomiting Coughing

Corticosteroids: Contraindications Contraindicated in children younger than 4 years Cautious use in pregnancy and lactation, and in those with immune system infections, tuberculosis, herpes simplex, ulcers, and nasal surgery or trauma

Corticosteroids: Patient Information Advise patients to avoid exposure to chickenpox or measles.

Leukotriene Inhibitors: Uses Block synthesis of, or the body’s inflammatory response to, leukotrienes Used in prophylaxis and treatment of chronic asthma or allergic rhinitis

Leukotriene Inhibitors: Adverse Effects Arrhythmias Dizziness Anxiety Headache Euphoria Dry mouth

Leukotriene Inhibitors: Contraindications Contraindicated in those with severe asthma attacks, bronchoconstriction, status asthmaticus, or during lactation Cautious use in children younger than 1 year, pregnancy, and patients with severe liver disease

Leukotriene Inhibitors: Patient Information Instruct patients not to use for severe asthma attacks.

Oral Administration Advantage The advantage of leukotrienes is oral administration. Some patients (especially children) do not adhere to inhaled medication therapy.

Mast Cell Stabilizers: Uses Inhibit release of bronchoconstrictors such as histamine from pulmonary mast cells Used for prophylaxis of mild to moderate seasonal and perennial bronchial asthma and allergic rhinitis; prevention of exercise-related bronchospasm; prevention of acute bronchospasm

Mast Cell Stabilizers: Adverse Effects Nausea and vomiting Dry mouth Throat irritation Cough Hoarseness

Mast Cell Stabilizers: Adverse Effects Headache Dizziness Urticaria Rash

Mast Cell Stabilizers: Contraindications Contraindicated in patients with coronary artery disease or history of arrhythmias, dyspnea, acute asthma, and status asthmaticus; during pregnancy; or in children younger than 6 years Cromolyn should be used cautiously in those with renal or hepatic dysfunction.

Mast Cell Stabilizers: Patient Information Advise patients to gargle with water or to suck on lozenges after each treatment to reduce throat irritation, cough, and hoarseness.

Table 28-2 Major Types of Cough Suppressants

Antitussives: Uses Opioids work by causing respiratory depression; nonopioids reduce activity of peripheral cough receptors and appear to increase threshold of central cough center Opioids are used to suppress nonproductive cough; nonopioids offer temporary relief of cough spasms.

Antitussives: Adverse Effects Difficulty breathing Drowsiness Rash Itching Dizziness Nausea Nervousness and restlessness

Antitussives: Contraindications Contraindicated in asthma, emphysema, diabetes, heart disease, seizures, thyroid conditions, chronic bronchitis, and liver disease Cautious use in pregnancy and lactation

Antitussives: Patient Information Advise patients to call physician if coughing continues longer than 1 week or mucus is yellow.

Natural Expectorant Wild cherry bark acts as an expectorant and a mild sedative. It is available in syrup or tincture forms. It should not be used during pregnancy.

Opioids for Cough Opioid analgesics are among most effective drugs used as cough suppressants: 15-mg doses are often sufficient.

Table 28-3 Expectorants and Mucolytics

Expectorants and Mucolytics: Uses Work by lowering viscosity and facilitating removal of mucous secretions (acetylcysteine) or enhancing reflex outflow of respiratory tract fluids by irritating gastric mucosa (guaifenesin) Used to treat bronchopulmonary disease and cystic fibrosis

Expectorants and Mucolytics: Adverse Effects and Contraindications Common adverse effects: very few Contraindicated in pregnancy and lactation Guaifenesin may interact with heparin.

Expectorants and Mucolytics: Patient Information Instruct patients to increase fluid intake. Tell patients to report a persistent cough beyond 1 week.

Table 28-4 The Most Commonly Used Decongestants

Table 28-4 (continued) The Most Commonly Used Decongestants

Decongestants: Uses Vasoconstricting agents that shrink swollen mucous membranes of nasal airway passage Used for relief of nasal congestion due to common cold, upper respiratory allergies, and sinusitis

Decongestants: Adverse Effects Nervousness and restlessness Insomnia Dizziness Headache Irritability

Decongestants: Contraindications Diabetes Heart disease Uncontrolled hypertension Hyperthyroidism Prostatic hypertrophy Concomitant use of other sympathomimetic drugs

Decongestants: Patient Information Instruct patients to avoid taking oral decongestants with 2 hours of bedtime because they may act as stimulants. Advise patients to discontinue and immediately report extreme. restlessness or signs of sensitivity Women should not breast feed.