Pharmacology II – Respiratory and Oxygenation Kathy Plitnick RN PhD CCRN Georgia Baptist College of Nursing of Mercer University

Antitussives Suppress cough Suppress cough Narcotics Narcotics Codeine Codeine Non-Narcotics Non-Narcotics Dextromethorphan Dextromethorphan Use: dry, nonproductive cough Use: dry, nonproductive cough

Dextromethorphan Available over-the-counter Available over-the-counter Chemically related to opiates Chemically related to opiates Contraindicated in chronic cough Contraindicated in chronic cough Caution in hepatic failure Caution in hepatic failure Rare Side Effects Rare Side Effects Interacts with other CNS depressants, Amiodarone, Quinidine, Alcohol Interacts with other CNS depressants, Amiodarone, Quinidine, Alcohol

Decongestants Relieve nasal obstruction Relieve nasal obstruction Adrenergic drugs Adrenergic drugs Constrict arterioles, reduce blood flow Constrict arterioles, reduce blood flow Mainly alpha receptors Mainly alpha receptors Oral, topical (sprays & drops) Oral, topical (sprays & drops) Use: relieve rhinitis, preop nasal surgery Use: relieve rhinitis, preop nasal surgery Contraindicated: HTN, CAD, glaucoma Contraindicated: HTN, CAD, glaucoma Sudafed (pseudoephedrine) Sudafed (pseudoephedrine) Large doses: tachycardia, palpitations, lightheadedness Large doses: tachycardia, palpitations, lightheadedness

Antihistamines Prevent effects of histamine Prevent effects of histamine Inhibit smooth muscle constriction Inhibit smooth muscle constriction Decrease capillary permeablity Decrease capillary permeablity Decrease salivation Decrease salivation Use: allergic rhinitis, anaphylaxis, drug allergies, transfusions, dermatologic, motion sickness, sleep Use: allergic rhinitis, anaphylaxis, drug allergies, transfusions, dermatologic, motion sickness, sleep Contraindicated: glaucoma, prostatic hypertrophy, pregnancy, bladder obstruction Contraindicated: glaucoma, prostatic hypertrophy, pregnancy, bladder obstruction

First Generation H1 Blockers Bind to central & peripheral H1 receptors Bind to central & peripheral H1 receptors CNS depression/stimulation CNS depression/stimulation Anticholinergic effects Anticholinergic effects Interact with alcohol, CNS depressants Interact with alcohol, CNS depressants Safety precautions Safety precautions Baseline assessment Baseline assessment Increase oral fluid intake Increase oral fluid intake No driving No driving

Diphenhydramine (Benadryl) High incidence of drowsiness High incidence of drowsiness Short term management - insomnia Short term management - insomnia Topical, oral, IM, IV Topical, oral, IM, IV Hypotension Hypotension Half-life 1-4 hours Half-life 1-4 hours

Second Generation H1 Blockers Produce less sedation Produce less sedation Less CNS depression Less CNS depression Fexofenadine (Allegra) Fexofenadine (Allegra) Rapid absorption Rapid absorption Half-life 14.4 hours Half-life 14.4 hours Caution in impaired renal function Caution in impaired renal function Obtain thorough history of allergic reaction Obtain thorough history of allergic reaction Baseline pulmonary assessment Baseline pulmonary assessment Administration with food Administration with food Safety measures Safety measures

Expectorants Liquefy secretions Liquefy secretions OTC preparations OTC preparations Guaifenesin (Robitussin) Guaifenesin (Robitussin) Decreases adhesiveness, surface tension Decreases adhesiveness, surface tension Well absorbed Well absorbed Symptomatic relief of cough Symptomatic relief of cough Do not use with persistent cough Do not use with persistent cough Rare side effects Rare side effects Assess type, severity of cough Assess type, severity of cough Increase fluid intake, Humidity Increase fluid intake, Humidity

Mucolytics Inhalation – liquefy mucus Inhalation – liquefy mucus Nebulized, Direct instillation Nebulized, Direct instillation Acetylcysteine (Mucomyst) Acetylcysteine (Mucomyst) Reduces viscosity Reduces viscosity Acetaminophen overdose Acetaminophen overdose Effective in 1 minute Effective in 1 minute Transient odor, irritated throat, N/V, bronchospasm Transient odor, irritated throat, N/V, bronchospasm

Bronchodilators Adrenergic drugs that stimulate beta2 receptors, stimulate adenyl cyclase, increase production of cAMP, produces bronchodilation Adrenergic drugs that stimulate beta2 receptors, stimulate adenyl cyclase, increase production of cAMP, produces bronchodilation Xanthines: Theophylline Xanthines: Theophylline Inhibits phosphodiesterase Inhibits phosphodiesterase Inhibits pulmonary edema Inhibits pulmonary edema Helps cilia clear mucus Helps cilia clear mucus Strengthens diaphragm Strengthens diaphragm

Theophylline Contraindicated: gastritis, PUD Contraindicated: gastritis, PUD Uses: asthma, bronchitis, emphysema Uses: asthma, bronchitis, emphysema Aminophylline by continuous infusion Aminophylline by continuous infusion Administer with water, after meals Administer with water, after meals Monitor plasma levels: mcg/ml Monitor plasma levels: mcg/ml Avoid smoking Avoid smoking Signs of toxicity: anorexia, N/V, dizziness, shakiness, restlessness, tachycardia, hypotension, seizures Signs of toxicity: anorexia, N/V, dizziness, shakiness, restlessness, tachycardia, hypotension, seizures

Beta Agonists – Albuterol Available oral, inhalation Available oral, inhalation Bronchodilation occurs 5-15 minutes Bronchodilation occurs 5-15 minutes Stimulates smooth muscle receptors in lungs, uterus, skeletal muscle Stimulates smooth muscle receptors in lungs, uterus, skeletal muscle Side Effects: throat irritation, palpitations, Tachycardia, hypertension, finger tremors Side Effects: throat irritation, palpitations, Tachycardia, hypertension, finger tremors Always administer prior to anti- inflammatory inhalers, steroids Always administer prior to anti- inflammatory inhalers, steroids

Anticholinergics : Ipratropium/Atrovent Block action of acetylcholine in bronchial smooth muscle Block action of acetylcholine in bronchial smooth muscle Reduces GMP Reduces GMP Halts bronchoconstriction due to PNS Halts bronchoconstriction due to PNS Administration by inhalation, intranasal Administration by inhalation, intranasal Ineffective in acute bronchospasm Ineffective in acute bronchospasm Adverse Effects: cough, nervousness, nausea, GI, headaches Adverse Effects: cough, nervousness, nausea, GI, headaches

Atrovent Do not use as an emergency agent Do not use as an emergency agent MDI’s – allow up to 1 minutes between puffs MDI’s – allow up to 1 minutes between puffs Rinse mouth after administration Rinse mouth after administration

Anti-inflammatory: Glucocorticoids/Beclomethasone Increase number of beta receptors Increase number of beta receptors Increase responsiveness of beta receptors Increase responsiveness of beta receptors Produces smooth muscle relaxation Produces smooth muscle relaxation Inhalation: decrease inflammatory cells, and swelling Inhalation: decrease inflammatory cells, and swelling Chronic asthma Chronic asthma Contraindicated: systemic fungal infections Contraindicated: systemic fungal infections

Beclomethasone Caution: active infection, DM, PUD, HTN, CHF, RI Caution: active infection, DM, PUD, HTN, CHF, RI Rinse mouth after administration Rinse mouth after administration Teach proper inhalation technique Teach proper inhalation technique Use bronchodilators first Use bronchodilators first

How Can You Avoid This Medication Error? Mr. C, 66 years old, has worsening COPD. At his last office visit, the MD added ipratropium (Atrovent) and beclomethasone (Vanceril) to his beta- adrenergic (Alupent) inhaler. He visits the office complaining of severe dyspnea. You quickly grab his Atrovent inhaler to administer a PRN dose and try to get him to relax. Mr. C, 66 years old, has worsening COPD. At his last office visit, the MD added ipratropium (Atrovent) and beclomethasone (Vanceril) to his beta- adrenergic (Alupent) inhaler. He visits the office complaining of severe dyspnea. You quickly grab his Atrovent inhaler to administer a PRN dose and try to get him to relax. What drug error has occurred, and how could this be avoided ?? What drug error has occurred, and how could this be avoided ??

Solution Acute dyspnea: only short-acting beta adrenergic bronchodilators should be used (Alupent) Acute dyspnea: only short-acting beta adrenergic bronchodilators should be used (Alupent) Teach which inhaler to use in an emergency Teach which inhaler to use in an emergency When prescribed multiple inhalers, canister should be a different color or marked in some way When prescribed multiple inhalers, canister should be a different color or marked in some way Know what the patient is prescribed Know what the patient is prescribed

Mast Cell Stabilizers: Cromolyn Sodium (Intal) No direct anti-inflammatory No direct anti-inflammatory Prevents release of mast cells after exposure to allergens Prevents release of mast cells after exposure to allergens Prophylactic mgmt severe asthma, seasonal rhinitis Prophylactic mgmt severe asthma, seasonal rhinitis Available oral, inhalation, nasal spray, ophthalmic Available oral, inhalation, nasal spray, ophthalmic

Cromolyn Sodium Use proper inhalation technique Use proper inhalation technique Wait 10 minutes between doses Wait 10 minutes between doses Rinse mouth after administration Rinse mouth after administration Assess respiratory status Assess respiratory status

Leukotriene Receptor Antagonists: Zafirlukast (Accolate) Binds to leukotriene receptors Binds to leukotriene receptors Inhibits bronchoconstriction Inhibits bronchoconstriction Reduces airway edema, smooth muscle constriction Reduces airway edema, smooth muscle constriction Rapidly absorbed Rapidly absorbed Half-life 10 hours Half-life 10 hours Chronic treatment Chronic treatment

Zafirlukast (Accolate) Aspirin increases concentration Aspirin increases concentration Warfarin increases PT Warfarin increases PT Monitor SGPT Monitor SGPT Side effects: headache, diarrhea, gastritis Side effects: headache, diarrhea, gastritis Baseline LFT’s Baseline LFT’s Assess respiratory function Assess respiratory function Increase fluid intake Increase fluid intake Not for acute episodes Not for acute episodes Take on empty stomach Take on empty stomach