Respiratory Medications NUR 2303 Week 12 PDF

Respiratory Medications NUR 2303 – Week 12 Housekeeping Questions Chapter 37 Antihistamines, Decongestants, Antitussives, and Expectorants Antihistamine Upper Respiratory Infections Most are caused by viral infection Excessive mucus production results from the inflammatory response Fluid...

Respiratory Medications NUR 2303 – Week 12 Housekeeping Questions Chapter 37 Antihistamines, Decongestants, Antitussives, and Expectorants Antihistamine Upper Respiratory Infections Most are caused by viral infection Excessive mucus production results from the inflammatory response Fluid drips down the pharynx into the esophagus and lower respiratory tract: sore throat, coughing, upset stomach Dilating small vessels in the nasal sinuses and causing congestion Treatment is symptomatic Avoid meds in children under 6 Histamine Major inflammatory mediator in many allergic disorders Allergic rhinitis (e.g., hay fever and mould and dust allergies) Anaphylaxis Angioedema Drug fevers Insect bite reactions Urticaria (pale red, raised, itchy bumps) Anaphylaxis Release of excessive amounts of histamine can lead to: Constriction of smooth muscle, especially in the stomach and lungs Increase in body secretions Vasodilatation and increased capillary permeability, movement of fluid out of the blood vessels and into the tissues, and drop in blood pressure and edema Antihistamines Drugs that directly compete with histamine for specific receptor sites: H1- smooth muscle contraction, dilation of capillaries H2 – accelerate heart rate and gastric acid secretion Histamine antagonists H1-antagonists (or H1-blockers) H2-antagonists (or H2 -blockers) Antihistamines and Histamine Antagonists H1-Antagonists (also called H1-blockers) chlorpheniramine, fexofenadine (Allegra®), loratadine (Claritin®), cetirizine (Reactine®), desloratadine (Aerius®), diphenhydramine (Benadryl®) H2-Blockers or H2-antagonists Used to reduce gastric acid in peptic ulcer disease cimetidine, ranitidine (Zantac®), famotidine (Pepcid AC®), nizatidine (Axid®) Antihistamines have several properties Antihistaminic Anticholinergic Sedative Antihistamines: Mechanism of Action Block action of histamine at H1-receptor sites Compete with histamine for binding at unoccupied receptors Cannot push histamine off the receptor if already bound The binding of H1-blockers to the histamine receptors prevents the adverse consequences of histamine stimulation. Vasodilation Increased gastrointestinal, respiratory, salivary, and lacrimal secretions Increased capillary permeability with resulting edema Should be given early in treatment before all the histamine binds to the receptors Histamine Effects Cardiovascular (small blood vessels) Histamine effects: dilation and increased permeability (allowing substances to leak into tissues) Smooth muscle (on exocrine glands) Histamine effects: stimulation of salivary, gastric, lacrimal, and bronchial secretions Immune system Histamine effects: mast cells release histamine and other substances, resulting in allergic reactions Antihistamines: Indications Nasal allergies Seasonal or perennial allergic rhinitis (hay fever) Allergic reactions Motion sickness Parkinson’s disease Vertigo Sleep disorders Antihistamines: Contraindications Acute-angle glaucoma Cardiac disease, hypertension Kidney disease Bronchial asthma, chronic obstructive pulmonary disease (COPD) Not to be used as sole drug therapy during acute asthmatic attacks Peptic ulcer disease Seizure disorders Benign prostatic hyperplasia Pregnancy Pediatric Considerations Fexofenadine hydrochloride is not recommended for children under 6 years of age or for those with kidney impairment. Desloratadine is not recommended for children. Loratadine is not recommended for children younger than 2 years of age. Antihistamines: Adverse Effects Anticholinergic (drying) effects: most common Dry mouth Difficulty urinating Constipation Changes in vision Cardiovascular, CNS, gastrointestinal, and other effects Drowsiness Mild drowsiness to deep sleep Antihistamines: Two Types Traditional: brompheniramine, chlorpheniramine, dimenhydrinate, diphenhydramine, and promethazine Nonsedating: loratadine, cetirizine, and fexofenadine Question Before administering an antihistamine to a patient, it is most important for the nurse to assess the patient for a history of which condition? A. Chronic urticaria B. Motion sickness C. Urinary retention D. Insomnia Traditional Antihistamines Work both peripherally and centrally Have anticholinergic effects, making them more effective than nonsedating drugs in some cases Examples: diphenhydramine, brompheniramine, chlorpheniramine, dimenhydrinate, promethazine Nonsedating Peripherally Acting Developed to eliminate unwanted adverse effects, sedation Work peripherally to block the actions of histamine; thus, fewer central nervous system adverse effects Longer duration of action (once-daily dosing) Examples: loratadine, cetirizine, and fexofenadine Antihistamines: Nursing Implications Instruct patients to report excessive sedation or hypotension. Instruct patients to avoid driving or operating heavy machinery, consuming alcohol or other CNS depressants. Instruct patients not to take these medications with other prescribed or OTC medications without checking with their prescribers. Best tolerated when taken with meals; reduces GI upset For dry mouth -gum, or hard candy Decongestants  Decongestants: Three Types Forms Adrenergics Oral Largest group Inhaled (topical) Sympathomimetics Anticholinergics Less commonly used Parasympatholytics Corticosteroids Topical, intranasal steroids Oral Decongestants Prolonged decongestant effects, but delayed onset Effect less potent than topical No rebound congestion Exclusively adrenergics Example: pseudoephedrine Topical Nasal Decongestants Prompt onset Potent Sustained use over several days causes rebound congestion, making the condition worse. Ephedrine, oxymetazoline (Dristan), Otrivin Intranasal Steroids and Anticholinergics Not associated with rebound congestion Often used prophylactically to prevent nasal congestion in patients with chronic upper respiratory tract symptoms Intranasal steroids beclomethasone dipropionate (Qvar®), budesonide (Rhinocort®), flunisolide (Rhinalar®), fluticasone (Avamys®), triamcinolone (Nasacort®), mometasone (Nasonex®) Intranasal anticholinergic ipratropium (Atrovent®) Nasal Decongestants: MOA Adrenergics Constrict small blood vessels that supply upper respiratory tract As a result, these tissues shrink, and nasal secretions in the swollen mucous membranes are better able to drain. Nasal steroids Anti-inflammatory effect Work to turn off the immune system cells involved in the inflammatory response Decreased inflammation results in decreased congestion. Nasal Decongestants: Effects and Indications Shrink engorged nasal mucous membranes Relieve nasal stuffiness Relief of nasal congestion associated with: Acute or chronic rhinitis Common cold Sinusitis Hay fever Other allergies Reduce swelling and facilitate visualization of the nasal or pharyngeal membranes before surgery or diagnostic procedure Nasal Decongestants: Contraindications Drug allergy Hx of CVA or TIA Acute-angle glaucoma Cerebral arteriosclerosis Uncontrolled CVD, HTN Long-standing asthma Diabetes and hyperthyroidism Benign prostatic hyperplasia Inability to close the eyes Diabetes Nasal Decongestants: Adverse Effects Adrenergics Nervousness Insomnia Palpitations Tremors Steroids Local mucosal dryness and irritation Nasal Decongestants: Nursing Implications Patients should avoid caffeine and caffeine-containing products. Patients should report a fever, cough, or other symptoms lasting longer than 1 week. Monitor for intended therapeutic effects. Question Kevonne, who is 55 years old, is asking for a decongestant to treat her allergies. She has a history of hypertension, which is controlled by medication. How will the nurse respond to Kevonne’s request for a decongestant? Antitussives Coughing Most of the time, coughing is beneficial. Removes excessive secretions Removes potentially harmful foreign substances In some situations, coughing can be harmful, i.e. hernia repair Productive cough: congested; removes excessive secretions Nonproductive cough: dry cough Antitussives Drugs used to stop or reduce coughing Opioid and nonopioid Primarily used only for nonproductive coughs May be used in cases when coughing is harmful Antitussives: Mechanism of Action Suppress the cough reflex by direct action on the cough centre in the medulla Analgesia, drying effect on the mucosa of the respiratory tract, increased viscosity of respiratory secretions, reduction of runny nose and postnasal drip Examples of opioid codeine hydrocodone Example of non-opioid - dextromethorpan Antitussive: Adverse Effects Should not drive a car or heavy equipment Used with caution due to CNS depression Nausea, Vomiting, Light-headedness, and Constipation Dizziness, drowsiness Dry motion Expectorants Expectorants Drugs that aid in the expectoration (removal) of mucus Reduce the viscosity of secretions with productive cough Disintegrate and thin secretions Example: guaifenesin (Robitussin) Expectorants: Mechanisms of Action Reflex stimulation Irritation of the gastrointestinal tract Loosening and thinning of respiratory tract secretions occur Direct stimulation The secretory glands are stimulated directly to increase their production of respiratory tract fluids. Result: thinner mucus that is easier to remove Expectorants: Nursing Implications Expectorants should be used with caution in older adults and patients with asthma or respiratory insufficiency. Patients should receive more fluids, if permitted, to help loosen and liquefy secretions. Report a fever, cough, or other symptoms lasting longer than 1 week. Monitor for intended therapeutic effects. Question Jabary, who is 14 years old, is complaining of a runny nose and itchy eyes. He has a history of seasonal allergies and takes loratadine (Claritin) as needed. Jabary has an allergy to penicillin and sulfa drugs. What medication would the nurse recommend for Jabary? Case Study: Summer Camp The camp nurse sees campers throughout the day to administer routine medications. In addition, the nurse provides various over- the-counter (OTC) medications as needed for cuts, scrapes, diarrhea, nausea, and various allergy complaints. The following patients have come to the clinic today: Sahid, who is 12 years old, is complaining of mosquito bites that itch. Sahid has no other health problems and no medication allergies. a. What medication would the nurse recommend for Sahid? b. What route would the nurse recommend? Chapter 38 Respiratory Drugs Asthma Occurs when the airways of the lungs become narrow: Bronchospasms Inflammation of the bronchial mucosa Production of viscous mucus The alveolar ducts and alveoli remain open, but airflow to them is obstructed. Status asthmaticus Prolonged asthma attack that does not respond to typical drug therapy May last several minutes to hours Medical emergency Chronic Obstructive Pulmonary Disease Progressive respiratory disorder Damage from inhaled particles, cigarette smoke Mucus hypersecretion, chronic cough, susceptibility to infection Characterized by chronic airflow limitation, scarring, thickening and consolidation Pharmacological Overview Bronchodilators Increased levels of cAMP (cyclic adenosine monophosphate) Relax bronchial smooth muscle, which causes dilation of the bronchi and bronchioles that are narrowed because of the disease process Three classes: β-adrenergic agonists, anticholinergics, and xanthine derivatives Non-bronchodilators Leukotriene receptor antagonists (montelukast, zafirlukast) Corticosteroids Mast cell stabilizers Bronchodilators: ß-Adrenergic Agonists Short-acting ß-agonist (SABA) inhalers salbutamol (Ventolin®) Terbutaline sulphate (Bricanyl®) Long-acting ß-agonist (LABA) inhalers formoterol (Foradil®, Oxeze®) salmeterol (Serevent®) Long-acting ß-agonist and glucocorticoid steroid combination inhaler budesonide/formoterol fumarate dihydrate (Symbicort®) Use as a reliever or rescue treatment for moderate to severe asthma when symptoms worsen ß-Adrenergic Agonists: Indications Relief of bronchospasm related to asthma, chronic obstructive pulmonary disease (COPD), and other pulmonary diseases Used in treatment and prevention of acute attacks Contraindications: Uncontrolled cardiac dysrhythmias High risk of stroke (because of the vasoconstrictive drug action) Adverse Effects: Sympathomimetic effects ß-Adrenergic Agonists: Interactions Diminished bronchodilation when nonselective ß-blockers are used with the ß-agonist bronchodilators Monoamine oxidase inhibitors Sympathomimetics Monitor patients with diabetes; an increase in blood glucose levels can occur. Salbutamol (Ventolin®) Short-acting ß2-specific bronchodilating ß-agonist Most used drug in this class Must not be used too frequently Oral, parenteral, and inhalational use Inhalational dosage forms include metered-dose inhalers as well as solutions for inhalation (aerosol nebulizers). Salmeterol (Serevent®) Long-acting ß2-agonist bronchodilator Never used alone, in combination with an inhaled steroid Used for the maintenance treatment of asthma and COPD; salmeterol max daily dose (one puff twice daily) should not be exceeded. Anticholinergics: Mechanism of Action Acetylcholine (ACh) causes bronchial constriction and narrowing of airways. Anticholinergics bind to the ACh receptors, preventing ACh from binding. Result: bronchoconstriction is prevented, airways dilate Also reduce secretions AKA muscarinic antagonists Anticholinergics ipratropium (Atrovent®), tiotropium bromide (Spiriva®) Indirectly cause airway relaxation and dilation Help reduce secretions in COPD patients Indications: prevention of the bronchospasm associated with COPD; not for the management of acute symptoms Anticholinergics: Adverse Effects Dry mouth or throat Nasal congestion Heart palpitations Gastrointestinal distress Urinary retention Increased intraocular pressure Headache Coughing Anxiety Xanthine Derivatives: Mechanism of Action Increase levels of energy-producing cyclic adenosine monophosphate (cAMP) This is done by competitively inhibiting phosphodiesterase, the enzyme that breaks down cAMP. Result: smooth muscle relaxation, bronchodilation Plant alkaloids: caffeine, theobromine, and theophylline Only theophylline and caffeine are currently used clinically. Synthetic xanthine: aminophylline Xanthine Derivatives: Drug Effects Cause bronchodilation by relaxing smooth muscle in the airways Relief of bronchospasm and greater airflow into and out of the lungs Also cause central nervous system stimulation Adverse effects: increased force of contraction and increased heart rate, resulting in increased cardiac output and increased blood flow to the kidneys (diuretic effect) Xanthine Derivatives: Indications Dilation of airways in asthmas and COPD Mild to moderate cases of acute asthma Not for management of acute asthma attack Adjunct drug in the management of COPD Not used as frequently because of potential for drug interactions and variables related to drug levels in the blood Contraindications: Uncontrolled cardiac dysthymias, seizure disorders, hyperthyroidism, peptic ulcers Xanthine Derivatives: Caffeine Used without prescription as a CNS stimulant or analeptic to promote alertness (e.g., for long-duration driving or studying) Cardiac stimulant in infants with bradycardia Enhancement of respiratory drive in infants in Neonatal Intensive Care Units (NICUs) Xanthine Derivatives: Theophylline Most used xanthine derivative Oral and injectable (as aminophylline) dosage forms Aminophylline: intravenous (IV) treatment of patients with status asthmaticus who have not responded to fast-acting ß-agonists such as epinephrine Therapeutic range for theophylline blood level is 55 to 100 mmol/L. Canadian Asthma Consensus guideline recommends levels between 28 to 55 mmol/L. Nonbronchodilating Respiratory Drugs Leukotriene receptor antagonists (montelukast, zafirlukast) Corticosteroids (beclomethasone, budesonide, dexamethasone, flunisolide, fluticasone, ciclesonide, and triamcinolone) Mast cell stabilizers: rarely used and no longer included in Canadian Asthma Management Continuum Small Group Activity Outline the process of how leukotriene modifiers block the inflammatory process. Leukotriene Receptor Antagonists: MOA Leukotrienes are substances released when there is a trigger Leukotrienes cause inflammation, bronchoconstriction, and mucus production. Leukotriene receptor antagonists prevent leukotrienes from attaching to receptors on cells in the lungs and in circulation. Inflammation in the lungs is blocked, and asthma symptoms are relieved. montelukast (Singulair®) zafirlukast (Accolate®) Leukotriene Receptor Antagonists: Effects Prevent smooth muscle contraction of the bronchial airways Decrease mucus secretion Prevent vascular permeability Decrease neutrophil and leukocyte infiltration to the lungs, preventing inflammation Leukotriene Receptor Antagonists: Indications Prophylaxis and long-term treatment and prevention of asthma Montelukast safe in children 2 years of age and older Zafirlukast safe in children 12 years of age and older Not meant for management of acute asthmatic attacks Montelukast is also approved for treatment of allergic rhinitis Improvement with their use is typically seen in about 1 week Contraindicated in those allergic to povidone, lactose, titanium dioxide, or cellulose derivatives May lead to liver dysfunction. Corticosteroids (Glucocorticoids) Anti-inflammatory properties Used in treatment of pulmonary diseases May be administered intravenously Oral or inhaled forms Inhaled forms reduce systemic effects. May take several weeks before full effects are seen Corticosteroids: Mechanism of Action Stabilize membranes of WBCs that release harmful bronchoconstricting substances (histamines, macrophages, etc.) ↑ responsiveness of bronchial smooth muscle to ß-adrenergic stimulation Dual effect of both ↓ inflammation and enhancing the activity of ß- agonists Inhaled Corticosteroids beclomethasone dipropionate (Qvar®) budesonide (Pulmicort Turbuhaler®) fluticasone furoate (Avamys®) fluticasone propionate (Flovent Dickus®) ciclesonide (Omnaris®) Inhaled Corticosteroids: Indications Control inflammatory responses that are believed to be the cause of these disorders Persistent asthma Often used concurrently with the ß-adrenergic agonists Systemic corticosteroids are generally used only to treat acute exacerbations or severe asthma. IV corticosteroids: acute exacerbation of asthma or other COPD Inhaled Corticosteroids: Contraindications Not intended as sole therapy for acute asthma attacks Hypersensitivity to glucocorticoids Patients whose sputum tests are positive for Candida organisms Patients with systemic fungal infection Inhaled Corticosteroids: Adverse Effects Pharyngeal irritation Coughing Dry mouth Oral fungal infections Systemic effects are rare because low doses are used for inhalation therapy. Inhaled Corticosteroids: Drug Interactions Drug interactions are more likely to occur with systemic (versus inhaled) corticosteroids. May increase serum glucose levels, possibly requiring adjustments in dosages of antidiabetic drugs May raise the blood levels of the immunosuppressants cyclosporine and tacrolimus; itraconazole may reduce clearance of the steroids phenytoin, phenobarbital, and rifampin Greater risk of hypokalemia with concurrent diuretic use (e.g., furosemide, hydrochlorothiazide) Discussion Discuss the sequencing of administration of inhaled drugs. Which drug would be indicated first, how long to wait before inhaling the second drug, and the significance of timing including the order of administration? Discuss the necessity of a spacer for both adult and pediatric clients. Nursing Implications: Broncodilators Avoiding exposure to conditions that precipitate bronchospasm (allergens, smoking, stress, air pollutants). Maintaining an adequate fluid intake Complying with medical treatment Avoiding excessive fatigue, heat, extremes in temperature, and caffeine. Teach patients to take bronchodilators exactly as prescribed. Ensure that patients know how to use inhalers and metered-dose inhalers, and have patients demonstrate the use of the devices. Nursing Implications: ß-Adrenergic Agonists Salbutamol, if used too frequently, loses its ß2-specific actions at larger doses. As a result, ß1-receptors are stimulated, causing nausea, increased anxiety, palpitations, tremors, and increased heart rate. Ensure that patients take medications exactly as prescribed, Inform patients to report insomnia, jitteriness, restlessness, palpitations, chest pain, or any change in symptoms Question Which medication will the nurse teach a patient with asthma to use when the patient is experiencing an acute asthma attack? A. salbutamol (Ventolin®) B. salmeterol (Serevent®) C. theophylline (Theolair®) D. montelukast (Singulair®) Nursing Implications: Xanthine Derivatives Contraindications: history of gastrointestinal disorders Cautious use with cardiac disease Timed-release preparations should not be crushed or chewed Be aware of drug interactions with cimetidine, oral contraceptives, allopurinol, certain antibiotics, influenza vaccine, and others. Cigarette smoking enhances xanthine metabolism. Interacting foods include charcoal-broiled, high-protein, and low- carbohydrate foods. These foods may ↓ serum levels of xanthines Nursing Implications: Leukotriene Receptor Antagonists Ensure that the medication is being used for long-term management of asthma, not acute asthma. Teach the patient the purpose of the therapy. Improvement should be seen in about 1 week. Advise patients to check before taking other meds. Assess liver function before beginning therapy. Teach patients to take medications every night on a continuous schedule, even if symptoms improve. Nursing Implications: Inhaled Corticosteroids Teach patients to gargle and rinse the mouth with warm water after. If a bronchodilator and corticosteroid inhaler are both ordered, the bronchodilator should be used several minutes before the corticosteroid to provide bronchodilation before administration of the corticosteroid. Teach patients to monitor disease with a peak flow meter. Encourage the use of a spacer device. Teach how to keep inhalers and nebulizer equipment clean. Question A patient with chronic bronchitis calls the office for a refill of a salbutamol inhaler. The patient, who just had the prescription filled 2 weeks ago, says the inhaler is empty. When asked, the patient tells the nurse, “I use it whenever I need it, but now when I use it, I feel so sick. I’ve been needing to use it more often.” What is the most appropriate action by the nurse? A. The nurse should confirm the pharmacy location for the needed refill. B. The nurse should ask the patient to come to the office for an evaluation of his respiratory status. C. The nurse should tell the patient not to use this drug too often. D. The nurse should consult the prescriber for a different inhaler prescription. Question The nurse is providing teaching to a group of individuals with chronic obstructive pulmonary disease at a community centre. Which statement by one of the attendees indicates that further teaching is needed? A. “If I develop a puffy face, I will stop taking methylprednisolone (Medrol®) immediately.” B. “I will inform my prescriber of any weight gain of 1 kg or more in 24 hours or 2.5 kg or more in 1 week.” C. “I use omalizumab (Xolair®) to control my asthma but not for an acute asthma attack.” D. “When taking theophylline (Theolair), I will advise my prescriber if I experience epigastric pain.” Take Home Reflection What is the rationale for the use of salbutamol and ipratropium for a client with COPD? Wrap-up Questions? Week 13: Substance Misuse, Drug Diversion, Misc Drugs