Drugs for Allergy and Respiratory Problems PDF
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This document provides information on drugs for allergy and respiratory problems, including learning outcomes, key terms, and examples.
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7 Drugs for Allergy and Respiratory Problems LEARNING OUTCOMES 1. Describe the causes and symptoms of allergy, asthma, and chronic obstructive pulmonary disease. 2. List the names, actions, possible side effects, and adverse effects of antihistamines, leukotriene inhibitors, and decongestant drugs....
7 Drugs for Allergy and Respiratory Problems LEARNING OUTCOMES 1. Describe the causes and symptoms of allergy, asthma, and chronic obstructive pulmonary disease. 2. List the names, actions, possible side effects, and adverse effects of antihistamines, leukotriene inhibitors, and decongestant drugs. 3. Explain what to teach patients and families about antihistamines, leukotriene inhibitors, and decongestant drugs. 4. List the names, actions, possible side effects, and adverse effects of beta-adrenergic agonists and anticholinergic antagonists for asthma and chronic obstructive pulmonary disease. 5. Explain what to teach patients and families about beta-adrenergic agonists and anticholinergic antagonists for asthma and chronic obstructive pulmonary disease. 6. Explain what to teach patients for correct use of drugs delivered by aerosol inhalers and drypowder inhalers. 7. Explain how asthma controller (preventive) drugs are different from asthma reliever (rescue) drugs. 8. List the names, actions, possible side effects, and adverse effects of mucolytic and antitussive drugs. 9. Explain what to teach patients and families about mucolytic and antitussive drugs. KEY TERMS allergy (Ă-lĕr-jē, p. 107) An excessive reaction that leads to an inflammatory response when a person comes into contact with a substance (allergen) to which he or she is sensitive. It is a common immune response to substances such as pollen, animal dander, food, or dust. Also known as hypersensitivity. antihistamine (ĂN-tī-HĬS-tă-mēn, p. 107) Drugs that stop histamines from attaching to histamine receptors in the tissues and producing inflammatory and allergic symptoms. This action counteracts the response of histamine in causing smooth muscle contraction and dilation and leakage of capillaries. antitussive (ĂN-tī-TŬ-sĭv, p. 121) Drugs that work to prevent and/or relieve coughing. 211 asthma controller drug (p. 115) Drugs that have the main purpose of preventing an asthma attack. Also known as asthma prevention drugs. These drugs must be taken daily even when no asthma symptoms are present. Also known as prevention drugs. asthma reliever drug (p. 115) Drugs that have the main purpose of stopping an asthma attack once it has started. Also known as asthma rescue drugs. bronchodilator (brn-k-D-l-trz, p. 115) Drugs that relax the airway smooth muscles allowing the lumen of the airways to widen. cholinergic antagonist (p. 116) Drugs that block the action of acetylcholine thereby inhibiting the parasympathetic nervous system response. Also known as cholinergic blockers, parasympatholytics, or anticholinergic drugs. corticosteroid (kōr-tĭ-kō-ˈSTĔR-oid, p. 112) Drugs built on the structure of cholesterol that are able to prevent or limit inflammation and allergy by slowing or stopping production of the mediators histamine and leukotriene. decongestant (dē-kăn-JĔS-tănt, p. 112) Drugs that reduce the swelling of nasal passages by shrinking the small blood vessels in the nose, throat, and sinuses so breathing is easier. leukotriene inhibitor (lū-kō-TRĪ-ēn ĭn-HĬ-bă-tĕr, p. 111) Drugs that block the leukotriene response and lessen or prevent the symptoms of allergy and asthma. long-acting beta-adrenergic agonist (LABA) (ă-dră-NĔR-jĭk Ă-gă-nĭst, p. 116) Orally inhaled drugs that bind over time to beta2-adrenergic receptors and are used as asthma controller drugs that must be taken on a daily schedule to prevent bronchospasms and asthma attacks even when symptoms are not present. mast cell stabilizer (cromone) (p. 112) Drugs that work on the surface of mast cells and prevent them from opening to release the inflammatory mediators. mucolytics (myū-kă-LĬ-tĭks, p. 119) Drugs that decrease the thickness of respiratory secretions and aid in their removal. Also called expectorants. short-acting beta-adrenergic agonist (SABA) (ă-dră-NĔR-jĭk Ă-gă-nĭst, p. 116) Orally inhaled drugs that bind rapidly to beta2-adrenergic receptors and can start smooth muscle relaxation within seconds to minutes. Also known as asthma reliever or rescue drugs. sympathomimetics (SĬM-pă-thō-mă-MĔ-tĭks, p. 112) Drugs that mimic the sympathetic nervous system and have the same actions as the body's own adrenalin. Also called beta- and/or alpha-adrenergic agonists. Allergy An allergy is an excessive reaction that leads to an inflammatory response when a person comes into contact with a substance or allergen to which he or she is sensitive. It is estimated that one in five people in the United States suffer from allergies. Allergens are usually harmless substances and include things people are surrounded with every day such as dust mites, plant pollen, pet dander, food, and 212 insect bites. These substances only cause allergic reactions in people who are overly sensitive to them. Allergies are also known as hypersensitivities and occur when the immune system overacts and develops a response to substances in the environment. When the immune system overreacts to an allergen, symptoms appear where the allergen entered or touched the body, usually in the nose, lungs, throat, or on the skin. The purpose of the immune system is to protect the body from living substances that cause infections such as bacteria, viruses, and fungi. The immune system also protects the body from nonliving substances it views as dangerous, such as drugs, toxins, and chemicals. These “invaders” are known as antigens because they are not part of the body and can trigger the immune system to take protective actions. These protective actions occur when the immune system produces an antibody directed against the offending antigen. The antibodies are produced by specific immune system cells known as lymphocytes in the bloodstream. The action of an antibody is to either neutralize the offending antigen or cause it to be destroyed and eliminated from the body. The lymphocytes make five different antibodies or immunoglobulins (Igs) for protection: IgA, IgD, IgE, IgG, and IgM. The IgE class of antibody is the body's defense against allergens. Once the antibodies are released in response to the allergen, they trigger other immune system cells and mast cells to produce internal chemicals, known as mediators, to start and continue inflammation. The important mediators released by WBCs when antibodies react with allergens are histamine and leukotriene. Histamine starts the inflammation and leukotriene works with histamine to keep the inflammatory response going once it has started. These mediators start actions in tissues and blood vessels resulting in inflammation and its symptoms. As described more completely in Chapter 11, these mediators, especially histamine, cause contraction of smooth muscle and dilation and leakage of capillaries, which explains the symptoms of swelling, redness, tissue irritation, and mucous production. Think about the person who has an allergy to pollens and develops hay fever. The symptoms include red, itchy eyes that produce tears to flush out the invader. The nasal passages swell, the nose is stuffed up to prevent entrance of more antigens, and the sinuses drain to get rid of the offender. Sneezing rids the invader from the airway passages. Contraction of the smooth muscle of the bronchioles or bronchoconstriction caused by histamine and by leukotriene release prevents entry into the lungs and causes breathing difficulties. Unfortunately, in an attempt to protect the body from the invaders, oxygen is also prevented from entering the body. Air must be able to move from the upper respiratory system (the oral and nasal cavities, sinuses, pharynx, larynx, and trachea) to the lower respiratory system (the bronchi and lungs) for gas exchange to take place. The alveoli in the base of the lungs exchange life-giving oxygen on inspiration for the waste product of carbon dioxide on expiration. Anything that interrupts this passage of air from the airway to the alveoli can cause death (Fig. 7.1). Disruptions that create problems can be a narrow or constricted opening (a bronchospasm), or a blockage from mucus, infection, or edema in the bases of the lungs (pulmonary edema) or collapse of the bronchioles and the alveoli themselves. 213 FIG. 7.1 The respiratory system. (From Herlihy B: The human body in health and illness, ed 5, St. Louis, 2014, Elsevier.) Drug Therapy for Allergy 214 Drugs used to treat allergies are those that interfere with inflammation. These include antihistamines, leukotriene blockers, and corticosteroids. Leukotrienes are also used to treat asthma because allergies often trigger asthma attacks. Decongestants are other drugs that can help lessen the symptoms of allergy but do not interfere with inflammation. Drugs used for allergies may be taken orally, used as a nasal spray, or inhaled into the lungs when inflammation triggers asthma. They can also be applied topically to the skin when allergic reactions are present in the skin. Table 7.1 lists the common drugs for allergy together with the nursing implications. Table 7.1 Examples of Common Antihistamines, Leukotriene Inhibitors, and Mast Cell Stabilizers First-generation antihistamines: work by preventing histamine from attaching to the tissue receptor sites, thus decreasing allergic symptoms. These drugs have safety concerns because they cause CNS depression. DRUG/ADULT DOSAGE RANGE NURSING IMPLICATIONS diphenhydramine (Benadryl) 25–50 mg orally three to four times a day or • Warn patients not to drive or operate hazardous equipment because these 10–50 mg slow IM or slow IV over 10 minutes every 4–6 hours PRN drugs usually cause drowsiness. diphenhydramine cream (topical agent) • Check the urine output of patients who have an enlarged prostate gland brompheniramine (Dimetapp) 12–24 mg orally once daily (oral) or 10 mg because a side effect of these drugs is urinary retention. IV slowly, IM, or subcutaneously every 6–12 hours PRN • Avoid giving these drugs to patients with glaucoma because the action can increase intraocular pressure. • Warn patients that many over-the-counter sleep aids contain first-generation antihistamines and taking these with an antihistamine could lead to overdose. • Watch for hyperexcitability and restlessness in children or older adults because they are more likely to have a paradoxical reaction to the drug. • Tell patients who are breast-feeding to avoid brompheniramine because it enters breast milk and will produce side effects in the infant. • Warn patients not to take these drugs with sedatives, opioids, anticholinergic drugs, or drugs that cause CNS depression because the CNS side effects will be more severe. • Warn patients to take these drugs for 2 weeks or less to avoid tolerance and long-term side effects. Second-generation antihistamines: work by preventing histamine from attaching to the tissue receptor sites, thus decreasing allergic symptoms. The incidence of CNS depression is much less with these antihistamines. DRUG/ADULT DOSAGE RANGE NURSING IMPLICATIONS fexofenadine (Allegra) 60 mg orally twice daily or 180 mg orally once • Teach patients not to take fexofenadine with grapefruit, orange, or apple daily juice because these products reduce the effectiveness of the drug. loratadine (Claritin) 10 mg orally once daily • Instruct patients taking the quick-dissolve tablets to place them under the levocetirizine (Xyzal) 2.5–5 mg orally once daily in the evening tongue and not to eat or drink until they have dissolved to promote best absorption. • Ask whether the patient has any kidney problems before giving either fexofenadine or levocetirizine because poor kidney function allows the drug to remain in the system longer and can lead to overdoses. • Check the urine output of patients who have an enlarged prostate gland because a side effect of these drugs is urinary retention. • Use cautiously with other drugs that cause sedation or CNS depression because, although these drugs have fewer CNS side effects, they may worsen the CNS depression of other drugs. • Give levocetirizine in the evening because it has more sedating effects than other second-generation antihistamines. Leukotriene inhibitors (modifiers): Zileuton (Zyflo) blocks production of leukotriene within white blood cells. Montelukast (Singulair) and zafirlukast (Accolate) block the leukotriene receptors on tissues. Both actions stop allergy symptoms and prevent the bronchoconstriction in asthma. DRUG/ADULT DOSAGE RANGE NURSING IMPLICATIONS montelukast (Singulair) 10 mg orally once a day at the same time • Teach patients to take zafirlukast 1 hour before or 2 hours after a meal zafirlukast (Accolate) 20 mg orally twice a day because the drug is best absorbed on an empty stomach. zileuton (Zyflo) 1200 mg orally twice daily, within 1 hour after morning • Teach patients to report any yellowing of the skin or eyes, darkening of the and evening meals urine, or white/gray stools because these drugs can impair the liver. • Warn patients and families to observe for changes in behavior or mood because all these drugs have been found to cause these problems in some patients. • These drugs are not to be used during an acute asthma attack because they require a long time to get to peak action. They are prevention rather than reliever drugs. Mast cell stabilizers (cromones): work by preventing mast cell membranes from opening and releasing histamine and leukotriene. DRUG/ADULT DOSAGE RANGE NURSING IMPLICATIONS cromolyn sodium (NasalCrom) 1 spray (5.2 mg/spray) in each nostril • Remind patients that there may be mild stinging or burning of the nasal three to four times per day; may be increased to six times a day if lining with use, but this is an expected side effect, not an allergy. needed or 20 mg oral inhalation by nebulizer every 6 hours • Teach patients to rinse the mouth and gargle after using the nebulizer to nedocromil sodium (Tilade) 2 inhalations (1.75 mg each) four times a day minimize dry mouth or throat, throat irritation, and hoarseness. • Remind patients that these drugs must be used as prescribed daily to reduce symptoms because they are not rapid-acting. 215 Bookmark This! Research is always expanding treatment and drugs. For more patient and healthcare professional education regarding allergens and asthma, check out the American Academy of Allergy, Asthma, & Immunology at https://www.aaaai.org. Antihistamines Actions Antihistamines are drugs that stop histamines from attaching to histamine receptors in the tissues and producing inflammatory and allergic symptoms. Allergens activate mast cells that are the chief controllers of the immune system. They are manufactured in the bone marrow and are present in all tissues of the body. When the mast cells are activated, they release histamine. There are two types of histamine: H1 and H2. Antihistamines do not prevent histamine from being released. They block the receptors on the tissues. Blocking H1 receptors limits the blood vessel vasodilation, capillary leak, swelling, and bronchoconstriction. Blocking H2 receptors decreases stomach acid production, which is discussed in Chapter 13. Antihistamines also limit the release of acetylcholine, which produces a drying effect (anticholinergic), particularly in the bronchioles and the GI system. Table 7.1 lists common antihistamines, their actions, and nursing implications. Uses Antihistamine H1-receptor blockers (antagonists) are used to treat almost any type of allergic reaction, including allergic rhinitis (nasal stuffiness and drainage). They are also used to treat asthma that is triggered by an allergic reaction. Histamine plays a central role in producing most of the typical eye and nasal signs and symptoms such as sneezing, nasal stuffiness, and postnasal drip. Antihistamines are classed as either first-generation drugs or second-generation drugs. First-generation drugs are available over the counter (OTC). Most of these products cross the blood–brain barrier and cause sedation (sleepiness) along with the antiallergy and anticholinergic effects. These drugs are effective in helping reduce symptoms of sneezing, itching, and rhinorrhea (runny nose) when used for a short time. Second-generation antihistamines are newer and usually have a more rapid onset of relief of sneezing, pruritus (itching), and rhinorrhea. These drugs do not cross the blood–brain barrier and thus do not cause significant sedation. Some are available by prescription and some are OTC. In general, they are less effective against nasal congestion than are first-generation drugs. Expected Side Effects Drowsiness is an expected side effect for most antihistamines. In fact many OTC sleep aids contain the antihistamine diphenhydramine. Patients should also expect dry mouth, increased heart rate, increased blood pressure, dilated pupils, and urinary retention to occur because of the anticholinergic effect of the antihistamines. 216 Adverse Effects Most adverse effects are related to severe anticholinergic symptoms, such as cardiac dysrhythmias or dangerously high blood pressure. A rising intraocular pressure (pressure inside the eye) in patients with glaucoma can worsen the disease and could cause blindness. Symptoms of overdosage include nervousness, anxiety, fear, agitation, restlessness, weakness, irritability, talkativeness, and insomnia. These symptoms may progress to dizziness, light-headedness, tremor, and hyperreflexia, with progression to confusion, delirium, hallucinations, and euphoria. Antihistamines, especially first-generation drugs, should be used with great caution in children because responses can be unpredictable. Problems with memory have been reported with continuous use of these agents, especially in older patients. Children and some older adults may have the opposite reaction (a paradoxical reaction) in which the patient has hyperexcitability, agitation, or confusion. Lifespan Considerations Older Adults Older adults often have pronounced anticholinergic effects such as constipation, dry mouth, and urinary retention (especially in men). Drug Interactions The sedative effect often seen with antihistamines is increased when other central nervous system (CNS) depressants (such as hypnotics, sedatives, tranquilizers, depressant analgesics, and alcohol) are used along with the antihistamine. The sedative effect of antihistamines also adds to the effect of anticholinergic drugs, and they can strengthen the anticholinergic side effects of monoamine oxidase inhibitors (MAOIs), as well as tricyclic antidepressants. When antihistamines are used along with ototoxic drugs (drugs that may damage hearing, such as large doses of aspirin or other salicylates, or streptomycin), the antihistamine may relieve some of the symptoms of ototoxicity, such as dizziness; as a result, these important symptoms may be masked. They may also interfere with the effects of anticholinesterase drugs. Nursing Implications and Patient Teaching Assessment. Ask the patient about the presence of drug allergy, other drug use, and the presence of asthma, glaucoma, peptic ulcer disease, prostatic hypertrophy, bladder neck obstruction, respiratory or cardiac disease, and the possibility of pregnancy. A patient with thyroid disease or migraine headaches may be unable to take antihistamines because of the tachycardia (rapid heartbeat) produced. These conditions are either contraindications or precautions for the use of antihistamines. 217 Planning and implementation. Antihistamines for allergy should be taken only when needed. The type and dose should be chosen for the desired effect and the person being treated. For example, first-generation drugs make people very sleepy, and people who do tasks that require alertness probably should not use them. This also is a concern in older patients who are prone to falls. Giving oral doses with food or drink can limit GI side effects; however, some antihistamines must be taken on an empty stomach. Check a drug reference guide to determine whether the drug can be given with food or certain liquids or if it needs to be taken on an empty stomach. When an IM preparation such as diphenhydramine is used, inject it deep into the muscle to prevent tissue irritation. Intravenous (IV) injection of these agents is done slowly, with the patient lying down because of the risk of the drug causing low blood pressure. Long-term use of topical nasal antihistamines increases the risk for sensitization, often causing a rebound effect, or an increase in the symptoms you are trying to stop. Evaluation. Assess the patient to determine whether allergy symptoms are reduced. Watch for any side effects. Assess older adults for side effects such as dizziness, syncope (light-headedness and fainting), and confusion. Problems with dyskinesia (difficulty in movements of the body), bradykinesia (slow movement), stiffness, and tremor are reactions that may also develop and must be reported to the prescriber. Patient and family teaching. Tell the patient and family the following: • Unless you must restrict your fluid intake because of another health problem, drink extra fluids to help prevent the respiratory tract dryness that often occurs with antihistamine use. • If any skin reactions occur, stop taking the drug at once and notify your healthcare provider. Do not increase the dose or drink alcohol while taking antihistamines because the CNS depressant effects of antihistamines may be increased. • Avoid tasks such as driving or activities that require alertness until you know how antihistamines affect you because they cause drowsiness in many patients. • If the drug causes stomach upset, take it with meals or milk to decrease this problem. 218 • You may develop tolerance to an antihistamine. If one drug seems to stop working over time, your healthcare provider may suggest trying another antihistamine for better control of symptoms. • Do not take any drugs without the knowledge of your healthcare provider, especially sedative drugs, while taking an antihistamine. Leukotriene Inhibitors Action Leukotriene inhibitors, sometimes called leukotriene modifiers, are drugs that block the leukotriene response and lessen or prevent the symptoms of allergy and asthma. Different leukotriene inhibitors have different actions to reduce inflammation. Zileuton (Zyflo) blocks production of leukotriene within white blood cells. Montelukast (Singulair) and zafirlukast (Accolate) block the leukotriene receptors on tissues. As a result of either action the inflammatory response is reduced. Table 7.1 lists common leukotriene inhibitors, their actions, and nursing implications. Uses Some leukotriene inhibitors are used for allergic rhinitis. Use of these inhibitors can relax respiratory smooth muscle and increase airflow through the bronchial tubes because leukotriene can also trigger bronchospasms. Thus these drugs also are used for prevention and long-term treatment of asthma. Expected Side Effects, Adverse Reactions, and Drug Interactions Leukotriene inhibitors are generally safe and well tolerated. Headache, nausea, and diarrhea are the most common side effects. Although adverse reactions to the leukotriene inhibitors are rare, liver dysfunction is possible with long-term use. The leukotriene inhibitors interact with drugs that stimulate liver metabolism such as phenytoin, phenobarbital, carbamazepine, and rifampin. Montelukast has the least amount of drug interactions. Nursing Implications and Patient Teaching Assessment. Ask the patient about the other drugs he or she takes. Ask about the possibility of pregnancy, breast-feeding, or liver disease. Planning and implementation. Leukotriene inhibitors are not started if the patient is having an acute asthma attack. They are drugs given as part of an asthma treatment regimen but will not relieve an acute attack of asthma. Watch to see whether there might be adverse drug interactions with other drugs the patient is taking. Some of these drugs are to be 219 given either with food or on an empty stomach. Evaluation. Therapeutic effect is usually seen within 3 to 7 days with a reduction in the number and severity of allergic reactions or asthma attacks. Patient and family teaching. Tell the patient and family the following: • Report any increase in asthma attacks or allergic symptoms to your healthcare provider. • Consider not taking these drugs if you are pregnant or breast-feeding, although this is an individual decision to be made by you and your healthcare provider based on risk and benefit. • These drugs are used to prevent (rather than stop) an asthma attack or allergic response; therefore do not suddenly stop taking the drug or decrease the dosage. Mast Cell Stabilizers (Cromones) Another type of drug that reduces the amount of histamine and leukotriene release and can be helpful for allergy or asthma is the class of mast cell stabilizers (cromones). They work on the surface of mast cells and prevent them from opening to release the inflammatory mediators. For nasal allergies and asthma they are used as inhaled drugs. Common cromones and their nursing implications are listed in Table 7.1. Decongestants Actions and Uses Nasal congestion occurs either because the nasal tissue is inflamed and swollen or because nasal secretions are thick and obstruct the nasal passage. Decongestants are drugs that reduce the swelling of nasal passages. There are two kinds of decongestants: sympathomimetic and corticosteroids. Sympathomimetics are drugs that produce or mimic stimulation of the sympathetic (adrenergic) nervous system and have the same action as the body's own adrenaline. When blood vessels are stimulated by the sympathetic nervous system (alpha receptors), they shrink (constrict). Once the blood vessels shrink, the secretions in the membranes of the nose can drain better and stuffiness and pressure are relieved. These drugs may also be used to decrease congestion around the eustachian tubes with middle ear infections. Most of these products are now available OTC. They can be taken orally or by nasal spray. Saline nasal spray and saline irrigations using a Neti Pot™ are an effective alternative to nasal sprays and 220 can be used routinely to relieve nasal symptoms. There are no side effects to the use of saline and it can be used as often as necessary. Corticosteroids are drugs built on the structure of cholesterol that are able to prevent or limit inflammation and allergy by slowing or stopping production of histamine and leukotriene. Corticosteroid nasal sprays are effective at controlling nasal inflammation. They stabilize the membranes of the white blood cells that produce histamine and leukotrienes that cause inflammation. They work on the white blood cells that help to fight infection; therefore their use is not recommended for people with sinus infections, or who have immune diseases or are taking immune-suppressing drugs. If they are absorbed systemically, it is possible for people to become ill because of the lessening response of infection-fighting white blood cells. It takes up to 2 weeks for corticosteroid nasal sprays to begin working. Oral, IV, and IM corticosteroids can also be used for allergic reactions but have many side and adverse effects. They may be used orally for allergies and asthma but are more commonly given as inhaled drugs. Table 7.2 lists common decongestants, their actions, and nursing implications. See Chapter 12 for a complete discussion of the actions and uses of corticosteroids, as well as the nursing responsibilities. Table 7.2 Examples of Common Decongestants Nasal corticosteroids: work to decrease inflamed and swollen nasal membranes by preventing mast cells and white blood cells within the nasal mucosa from releasing histamine, leukotriene, and other mediators of inflammation. DRUG/ADULT DOSAGE RANGE NURSING IMPLICATIONS fluticasone (Flonase, Sensimist) 2 sprays of 110 • Remind patients that relief is not immediate because these drugs take time to build up an effect. mcg once daily • Caution patients not to swallow the spray to prevent absorbing the drug systemically and causing triamcinolone (Nasacort) 2–4 sprays of 55 more side effects. mcg/spray once daily • Remind patients to clean and dry the applicator after each use (and never to share the inhaler with another person) to prevent infection because these drugs reduce the local immune response. • Tell patients to watch for white patches in the nose or throat that may indicate a fungal infection because these drugs reduce the local immune response. Sympathomimetic drugs: work to shrink swollen nasal membranes by activating the adrenergic receptors on the blood vessels within the nasal mucosa, causing them to constrict. Swelling is reduced and sinus drainage is improved. DRUG/ADULT DOSAGE RANGE NURSING IMPLICATIONS oxymetazoline, nasal spray (Afrin, many others), • Tell patients that relief of nasal congestion is immediate because these sprays and drops work on 2–3 sprays in each nostril PRN every 10–12 contact with nasal membranes. hours • Remind patients to use the nasal sprays for only a few days because tolerance and rebound phenylephrine, spray or drops (Neo-Synephrine, stuffiness occur quickly. many others), 0.5%–1% solution sprayed or • Caution patients not to swallow the spray to prevent absorbing the drug systemically and causing dropped into the nose every 6 hours more side effects. phenylephrine, oral tablets or liquids (Nasop, • Warn patients with high blood pressure, heart disease, glaucoma, or prostate enlargement to use Sudafed, many others), 10–20 mg every 6 hours these drugs with caution and not to exceed the prescribed dose because the drugs increase blood PRN pressure, cause urinary retention, and increase intraocular pressure. pseudoephedrine (Dimetapp, Sudafed, many • Suggest that patients who are using the oral forms of the drugs take them at least 4 hours before others) 60 mg orally every 6 hours or 120 mg going to bed because these drugs can cause insomnia. orally every 12 hours Uses Nasal decongestants are used to shrink nasal mucous membranes and relieve nasal congestion caused by allergies or cold symptoms. Expected Side Effects Topically applied nasal decongestants (sprays or drops) are well tolerated because the amount that enters the bloodstream is too small to cause side effects. Local effects include irritation and dryness of the mucous membranes. Sympathomimetic nasal spray that is overused can enter the bloodstream and cause nervousness, insomnia, tremors, and heart palpitations. Expected side effects of oral decongestants include headache, nervousness, dizziness, insomnia, and tremors. A slight nosebleed is 221 common with corticosteroid nasal sprays, but if it becomes severe, it would be considered an adverse effect. Adverse Reactions Oral sympathomimetic decongestants can have adverse side effects related to mimicking the sympathetic nervous system response. The sympathetic nervous system (beta1 receptors) increases heart rate, increases the force of contraction of the heart muscle, increases the speed of electrical conduction in the heart, and constricts the blood vessels. The adverse effects that can be seen are cardiac dysrhythmias, hypertension, and palpitations, which could lead to a heart attack. Sympathomimetic nasal decongestants can cause rebound congestion if overused or used more than 3 to 5 days. Rarely a severe shocklike syndrome with hypotension and coma has been reported in children. Psychological dependence and toxic psychoses have been reported with long-term, high-dose therapy. The severity of overdosage varies, resulting in a variety of symptoms. The US Food and Drug Administration (FDA) stipulates that these products are not to be used in infants and toddlers because of problems with inadvertent overdosage in this age group. Corticosteroid nasal sprays can reduce the protective immune responses in the nose and throat. This action increases the risk for upper respiratory infections and overgrowth of oral fungus (yeast). As a result, redness, sores, or white patches may appear in the mouth or throat. Drug Interactions Interactions for sympathomimetics include caffeine, MAOIs, amphetamines, ergotamine, selegiline, and linezolid, which can cause hypertension and increasing heart rate with dysrhythmias. These drugs should not be taken with beta-blocking eye drops used for open-angle glaucoma. Corticosteroid nasal sprays should not be used with antibiotics or immunosuppressive drugs. Nursing Implications and Patient Teaching Assessment. Monitor heart rate and blood pressure in people taking sympathomimetic drugs, especially in those with a history of cardiac disease. Notify the prescriber if rapid heart rate or irregular heart rate develops or if hypertension worsens. For people taking corticosteroid nasal spray, assess the nasal and mouth area for white patches or redness that may indicate a fungal infection. For people susceptible to infection, take their temperature and monitor any signs and symptoms that might indicate an infectious process rather than an allergy, that is, thick green nasal discharge, shortness of breath, or wheezing. Planning and implementation. Oral sympathomimetic drugs can decrease the effectiveness of some high blood pressure drugs and should not be used in persons with uncontrolled hypertension or cardiac insufficiency. Patients on antibiotics, antifungals, immunosuppressives, or HIV drugs or those who have a sinus infection should not use corticosteroid nasal sprays. 222 Evaluation. Nasal stuffiness and inflammation should be relieved instantly with sympathomimetic nasal spray and within an hour if taking oral sympathomimetics. Nasal corticosteroids can take up to 2 weeks to reduce symptoms. Patient and family teaching. Tell the patient and family the following: • Before using a decongestant, check with your prescriber if you have heart disease, high blood pressure, glaucoma, diabetes, an enlarged prostate, or thyroid disease because decongestants can make these problems worse. • Avoid the use of caffeine, alcohol, or other stimulant drugs while using oral sympathomimetic decongestants because heart rate and blood pressure problems will increase. • Avoid taking sympathomimetic drugs within 4 hours of bedtime because these drugs may cause insomnia. • If you develop extreme restlessness, insomnia, tremors, and heart palpitations, stop using the drug and notify your healthcare provider. • Do not take sympathomimetic drugs if you are pregnant or breast-feeding. • Do not overuse sympathomimetic nasal spray or use it for more than 3 days because a rebound stuffiness and congestion are likely to occur. • If you have high blood pressure or heart problems, check with the pharmacist before using OTC cold preparations that say they relieve nasal congestion or stuffiness because OTC cold preparations often contain sympathomimetic drugs. • If you have glaucoma or cataracts, check with your healthcare provider before using corticosteroid nasal sprays. • Contact your healthcare provider if white patches 223 develop in the nose or mouth, you have worsening nasal discharge, or flu symptoms and fever develop while taking corticosteroid nasal sprays. Asthma and Chronic Obstructive Pulmonary Disease Asthma Asthma is a long-term condition of the airways that causes smooth muscle constriction and inflammation of the airways and lungs. As a result of airway narrowing, airflow to lung tissue, where oxygen is picked up by the blood, can be greatly reduced. Although the actual symptoms of asthma may occur from time to time rather than continuously (known as an intermittent problem), the disorder is chronic and the person is always at risk for an asthma attack. However, the symptoms of asthma are reversible, and between attacks the patient usually has no signs or symptoms. Two different problems can make the airways smaller and become obstructed (Fig. 7.2). Internal airway obstruction occurs when inflammation, often caused by an allergy, causes the mucous membrane lining to swell and secrete extra mucus. In addition, when the smooth muscle surrounding the airway tightens (constricts), it narrows the outside structure of the airway through bronchoconstriction. Many patients with asthma actually have both types of airway obstruction because an allergy can irritate bronchiolar smooth muscle. Drug therapy for asthma usually requires more than one drug type to manage the two causes of the disorder. FIG. 7.2 Causes of narrowed airways: (A) Mucosal swelling. (B) Constriction of smooth muscle. (C) Mucosal swelling and constriction of smooth muscle. (D) Mucous plug. (From Workman ML, LaCharity LA, Kruchko SL: Understanding pharmacology, ed 1, St. Louis, 2011, Elsevier.) Memory Jogger Inflammation narrows airways from the inside, and bronchoconstriction narrows airways from the outside. Symptoms of an asthma attack are shortness of breath, wheezing (the whistling sound a vacuum makes when it becomes clogged), dry, hacking cough, or a feeling of tightness in the chest. Asthma episodes can occur frequently every day, a few times per week, during the day or night, with exercise, or on a seasonal basis. 224 Management depends on the severity and frequency of symptoms. Chronic Obstructive Pulmonary Disease Chronic obstructive pulmonary disease (COPD) is a progressive disease that causes breathing difficulty. It obstructs airflow passages in the upper and lower airways, which includes the alveoli, where gas exchange takes place. The usual cause of COPD is cigarette smoking or exposure to secondhand smoke and air pollution that causes a constant inflammation of the upper airways known as chronic bronchitis. The inflammation causes large amounts of sticky mucus to be produced, which obstructs the upper airways, makes the work of breathing very difficult, and prevents air from flowing into the lungs and alveoli. Bronchitis affects only the airways, not the alveoli. The same things that cause chronic bronchitis also cause the emphysema that is seen in COPD. Emphysema is damage to the lower airways and involves damage to the lung tissue and alveoli. When the alveoli become damaged, they can no longer stretch for oxygen to enter or shrink to force carbon dioxide out. The alveoli begin to collapse and die; the fewer alveoli that exist, the less oxygen is available to be moved into the bloodstream and the more carbon dioxide the body retains. COPD causes a chronic cough that produces clear, white, yellow, or green sticky mucus, wheezing, shortness of breath, chest tightness, and an enlarged chest. Unlike with asthma, the person diagnosed with COPD always has symptoms, but these become worse with increases in inflammation from pulmonary infections and in response to pollution and other triggers. Unlike asthma, the lung damage with COPD is not reversible, although patients may have periods with less severe symptoms. Drug therapy for COPD involves most of the same drugs used for asthma because the symptoms are similar, although the actual causes differ. Drug Therapy for Asthma and Chronic Obstructive Pulmonary Disease Drug therapy for both asthma and COPD includes bronchodilating and antiinflammatory agents. Although both types of drugs are used, when used for COPD the dosage and delivery method may be different (some drugs are more often delivered by nebulizer rather than as a sprayed inhalant). In addition, drugs that help thin secretions (mucolytics) are used more often in COPD therapy than in asthma therapy (discussed later in this chapter). The goals of drug therapy for asthma are to: (1) prevent acute asthma attacks, and (2) stop an asthma attack as quickly as possible after it has started. Thus some drugs are asthma controller drugs (prevention drugs) that have the main purpose of preventing an attack. Controller drugs must be taken daily to be effective, even when the person has no symptoms of asthma. Controller drugs usually include longer-acting bronchodilators, as well as drugs that prevent excessive inflammation (anti-inflammatories). Drugs that have the main purpose of stopping an asthma attack are asthma reliever drugs (rescue drugs). They are usually short-acting bronchodilators that have no role in asthma prevention. The Global Initiative for Asthma has published guidelines for asthma diagnosis and drug management. 225 These guidelines recommend a stepwise plan for using asthma drugs that takes into account asthma severity (Table 7.3). Table 7.3 The Step System for Drug Therapy in Asthma STEP 1 STEP 2 Daytime Daytime symptoms symptoms occur occur not more not more than than twice per twice per week week and do and do limit not limit activity. activity. Reliever drug Reliever drug needed not more needed not than twice more than twice weekly. weekly. As needed rapidAs needed rapidacting beta2 agonist acting beta2 agonist (relief inhaler) (relief inhaler) No daily drugs Daily treatment needed involves the use of one of these two options: Low-dose ICS Leukotriene receptor antagonist/inhibitor STEP 3 Daytime symptoms occur more than twice per week, nighttime symptoms also are present. Symptoms limit activity. Reliever drug needed more than twice weekly. STEP 4 Daytime symptoms occur more than twice per week, nighttime symptoms also are present. Symptoms limit activity. Reliever drug needed daily. As needed rapid-acting As needed rapid-acting beta2 agonist beta2 agonist (relief inhaler) (relief inhaler) STEP 5 Daytime symptoms occur daily, nighttime symptoms also are present. Symptoms limit activity. Reliever drug needed daily or more than once daily. As needed rapid-acting beta2 agonist (relief inhaler) Daily treatment Daily treatment involves the use of Daily treatment involves the use involves the use of one the Step 3 option that provided the of the Step 4 option(s) that of these four options: best degree of control and was well provided the best degree of Low-dose ICS and longtolerated along with one or more of control and was well tolerated acting beta2 agonist these two options: along with either of these two options: Medium- to high-dose ICS Medium-dose or high-dose ICS and long-acting beta2 agonist Oral glucocorticosteroid (lowest dose) Low-dose ICS and Anti-IgE treatment leukotriene receptor Leukotriene receptor antagonist/inhibitor antagonist/inhibitor and sustainedLow-dose ICS and low-dose release theophylline theophylline ICS, Inhaled corticosteroid; IgE, immunoglobulin E. Data compiled from Global Initiative for Asthma (GINA). (2017). Pocket guide for asthma management and prevention. Retrieved from http://ginasthma.org/2017-pocket-guide-for-asthma-management-and-prevention/ Memory Jogger Asthma controller drugs prevent asthma attacks and must be taken daily even when asthma symptoms are not present. Asthma reliever drugs can rescue a person having an actual asthma attack. They are used only as needed and not on a schedule. Bronchodilators Action Bronchodilators are drugs that relax the airway smooth muscles, allowing the lumen of the airways to widen. The respiratory and cardiac systems have special receptors (alpha and beta receptors) in the muscle cells that help in speeding up or slowing down the respiratory and cardiac processes. The main action of bronchodilators in asthma and other respiratory diseases when the airways are constricted is to act like the body's own adrenaline, which binds to and stimulates the beta2-adrenergic receptors within bronchial tube smooth muscle and allows them to relax. The most common class of drugs with this action are the beta2-adrenergic agonists. (Recall from Chapter 3 that an agonist drug binds to its receptor and activates it.) Another class of drugs that allows relaxation of bronchial smooth muscle is the cholinergic antagonists. (Recall from Chapter 3 that an antagonist drug 226 blocks a receptor rather than activates it.) Cholinergic drugs and agents (such as acetylcholine) have exactly the opposite action of adrenaline. So by giving a cholinergic antagonist, there is less acetylcholine present to interfere with the work of the body's adrenaline. This action allows natural adrenaline to bind to more beta2adrenergic receptors and causes relaxation of bronchial smooth muscle. They are also useful in decreasing the excessive thick and sticky secretions seen in chronic bronchitis. Uses The uses of bronchodilators in asthma and COPD depend on the drug's duration of action. Short-acting beta2-adrenergic agonists (SABAs) are orally inhaled drugs that bind rapidly to beta2-adrenergic receptors and can start smooth muscle relaxation within seconds to minutes. As a result, SABAs are used during an actual asthma attack and when the person with COPD has symptoms of bronchospasm. SABAs may also be used during other respiratory infections when patients experience bronchospasms. Thus SABAs are reliever drugs that act quickly. The effects also wear off quickly, and a person may need more than one dose to stop a bronchospasm or asthma attack. Examples of common SABAs are listed in Table 7.4. Table 7.4 Examples of Common Bronchodilators Short-acting beta2 agonists (SABAs): cause bronchodilation by rapidly binding to beta2-adrenergic receptors in bronchial smooth muscle and stimulating muscle relaxation quickly, which widens the airways. These are reliever/rescue inhaled drugs used either during an asthma attack or just before engaging in activity that usually triggers an attack. DRUG/ADULT DOSAGE RANGE NURSING IMPLICATIONS • Teach patients to carry the drug with them at all times because it can stop or reduce a lifealbuterol (Apo-Salvent , ProAir HFA, PMSthreatening asthma attack or bronchoconstriction. Salbutamol , Respirol, Ventolin HFA, • Teach patient to monitor heart rate and other responses because excessive use causes rapid heart VoSpire ER) 1–2 inhalations (90 mcg each) rate, nervousness, and tremors. every 4–6 hours PRN • When taking this drug with other inhaled drugs, teach patients to use this drug first and wait at least levalbuterol (Xopenex) 1–2 inhalations (45 mcg 5 minutes before taking the other inhaled drugs to allow the bronchodilating effect to increase the each) every 4–6 hours movement of the other drugs into the lungs. pirbuterol (Maxair) 2 inhalations (0.4 mg each) • Teach patients to use the directions in Box 7.1 for correct technique to ensure the drug reaches the every 4–6 hours airways. • Instruct patients to use a spacer with the metered-dose inhalers (MDIs). If a spacer is not available, teach them to hold the mouthpiece 1–2 inches away from the mouth when the inhaler is activated and then to inhale the mist so that the drug reaches the airways and does not just stick to the back of the throat. Long-acting beta2 agonists (LABAs): cause bronchodilation by binding to beta2-adrenergic receptors in bronchial smooth muscle over time and eventually stimulating continued smooth muscle relaxation. These are controller/prevention inhaled drugs used to prevent an asthma attack or bronchospasm. LABAs are not to be used as a rescue drug. DRUG/ADULT DOSAGE RANGE NURSING IMPLICATIONS arformoterol (Brovana) 15 mcg every 12 hours (1 • Remind patients to use LABAs daily as prescribed, even when symptoms are not present, to prevent vial) via nebulizer an asthma attack or bronchospasm. formoterol (Foradil, Oxeze, Perforomist) 12 mcg • Remind patients to not use LABAs as reliever/rescue drugs because their onset of action is too slow (one capsule) every 12 hours by DPI to help in an acute attack. salmeterol (Serevent) 50 mcg (1 inhalation) every • Teach patients using a dry-powder inhaler (DPI) to follow the instructions in Box 7.2 and the 12 hours by DPI directions on the inhaler to ensure best effect of the drug. Cholinergic antagonists: are inhaled controller drugs that cause bronchodilation by preventing the nervous system from releasing some acetylcholine, which then allows more of the body's own adrenaline to activate beta2 receptors in bronchial smooth muscle. DRUG/ADULT DOSAGE RANGE ipratropium (Atrovent) 2–4 inhalations (17 mcg each) over 6–8 hours tiotropium (Spiriva HandiHaler) 1 inhalation (18 mcg) every day by DPI tiotropium (Spiriva Respimat) 2 inhalations (2.5 mcg) daily by MDI NURSING IMPLICATIONS • Teach patients using an MDI to shake it well before using because the drug separates easily. • Teach patients to drink plenty of liquids because the drugs cause mouth dryness. • Teach patients about the expected side effects of stuffy nose, sore throat, and constipation because knowing the side effects helps relieve anxiety when they appear. • Instruct patients to report urinary retention or consistently increased heart rate to their healthcare provider because these are serious adverse effects of the drugs. Indicates Canadian drug. 227 Top Tip for Safety Teach patients with asthma to always have their SABA reliever drug with them at all times because an attack can occur anywhere and only an SABA can work fast enough to prevent a severe attack and death. Some beta2-adrenergic agonists are long-acting. Although they work in the same way as SABAs, they take time to build up an effect and the effect lasts longer. These long-acting beta2-adrenergic agonists (LABAs) are orally inhaled drugs that bind over time to beta2-adrenergic receptors and are used as asthma controller drugs that must be taken on a daily schedule to prevent bronchospasms and asthma attacks even when symptoms are not present. LABAs are not helpful during an acute attack because they take time to work. Examples of common LABAs are shown in Table 7.4. At times, so that patients have fewer drugs to take and remember, an LABA may be combined with an inhaled corticosteroid together in one inhaler. An example is Breo Ellipta, which is the LABA vilanterol combined with the inhaled corticosteroid fluticasone. Memory Jogger SABAs are reliever (rescue) drugs that are effective in stopping an actual asthma attack or bronchospasm. LABAs and cholinergic antagonists are controller (prevention) drugs and are not helpful during an asthma attack or bronchospasm. Memory Jogger Activated beta1-adrenergic receptors and beta1 agonist drugs increase heart rate, force of contraction, and speed of conduction (hint: you have only one [1] heart). Activated beta2-adrenergic receptors and beta2 agonist drugs cause bronchodilation (hint: you have two [2] lungs). Activated alpha-adrenergic receptors or alpha agonists cause vasoconstriction. Cholinergic antagonists are also used as orally inhaled controller drugs. Their response is slower, but they work by relaxing the muscles around the airways so the airway can open wider and breathing is improved. Just like LABAs, cholinergic antagonists cannot stop an asthma attack or a bronchospasm once it has started. Examples of common cholinergic antagonists are shown in Table 7.4. Xanthine-based drugs are an older type of bronchodilator that are given systemically and are rarely used because the dose that is effective is close to the dose that produces many dangerous side effects. This class of drug includes theophylline and aminophylline. They are used only when other types of management are not effective. Patients must have blood levels drawn frequently to ensure that the drug level is within the therapeutic range and not in the toxic range. The use of xanthines is not within the scope of this chapter. 228 Expected Side Effects Orally inhaled bronchodilators usually have few and only mild side effects because most of the drug goes to the airways. The action of all types of bronchodilators results in the stimulation of both beta1-adrenergic and beta2-adrenergic receptors throughout the body, especially in the heart and blood vessels; therefore when bronchodilators are heavily used, common side effects include hypertension, tachycardia, headache, and insomnia. Some people feel “nervous” and may have tremors with these drugs. Dry mouth and a bad taste are common side effects. Cardiovascular side effects are more noticeable with the SABAs because the onset of action is so rapid. Adverse Reactions With inhalers that contain a preservative, patients may have allergic reactions (to the preservative). Also, if the bronchodilator is heavily used, it can be absorbed throughout the body and cause constriction of blood vessels in the heart muscle, leading to chest pain or even a myocardial infarction (heart attack). Drug Interactions Drug interactions may occur with MAOIs, tricyclic antidepressants, beta blockers (beta-adrenergic antagonists), other antihypertensive agents, digoxin, potassiumlosing diuretics, and caffeine-containing herbs. The combination of two or more of these agents may produce an additive effect. Many general anesthetics may cause dysrhythmias when they are used with these drugs. Nonselective beta blockers and beta-adrenergic blocking agents such as propranolol (Inderal) may block the bronchodilating effects of these beta2 receptor– stimulating drugs. Bronchodilators can interfere with the action of some antihypertensive drugs. Nursing Implications and Patient Teaching Assessment. Ask whether the patient is pregnant, breast-feeding, or has a history of hyperthyroidism, heart disease, hypertension, diabetes, glaucoma, seizures, or psychoneurotic disease. Ask whether the patient is taking other drugs that may interact with bronchodilators or has a history of allergy. Any of these conditions may present contraindications or precautions to the use of bronchodilators. Take a baseline set of vital signs to be able to assess for drug-related changes. Planning and implementation. Beta2-adrenergic receptors in bronchial smooth muscle cells must be stimulated to relieve bronchial spasm. One of the drawbacks of bronchodilators is they may also stimulate receptors in the heart (beta1), which increases the rate and force of cardiac contraction. Thus bronchodilators should be given with extreme caution to patients who already have cardiovascular, endocrine, or convulsive disorders that may be affected by these drugs. The routes of administration of bronchodilators vary according to how ill the 229 patient is (the diagnostic classification) and the preparation to be used. Drugs may be given parenterally, orally, or, most often, by oral inhalation (nebulizers or metered-dose inhalers [MDIs]). How well the orally inhaled drug works to control or relieve asthma and bronchospasm depends on correct use of the inhaler. Show a patient who is using an inhaler for the first time how to use the inhaler and give written instructions to refer to later. Research shows that many patients do not use inhalers correctly, so every time the patient comes in for a healthcare visit, ask for a demonstration of how the MDI is being used. Fig. 7.3 shows MDIs. Box 7.1 describes how to use an MDI, and Fig. 7.4 shows a patient using the inhaler with a spacer. Fig. 7.5 shows a typical dry-powder inhaler, and Box 7.2 describes how to use it. See Chapter 4 for instructions regarding the use of a nebulizer to deliver orally inhaled drugs. FIG. 7.3 Metered-dose inhalers with counter. (From Patel, M., Pilcher, J., Travers, J., et al. (2013). Use of Metered-Dose Inhaler Electronic Monitoring in a Real-World Asthma Randomized Controlled Trial. The Journal of Allergy and Clinical Immunology: In Practice, 1(1), 83–91.) Box 7.1 Teaching a Patient How to Correctly Use a Metered-Dose Inhaler With a Spacer (Preferred Technique) 1. Before each use, remove the caps from the inhaler and the spacer. 2. Insert the mouthpiece of the inhaler into the nonmouthpiece end of the spacer. 3. Shake the whole unit vigorously three or four times. 4. Fully exhale and then place the mouthpiece into your mouth, over your tongue, and seal your lips tightly around it. 230 5. Press down firmly on the canister of the inhaler to release one dose of the drug into the spacer. 6. Breathe in slowly and deeply. If the spacer makes a whistling sound, you are breathing in too rapidly. 7. Remove the mouthpiece from your mouth and, keeping your lips closed, hold your breath for at least 10 seconds and then breathe out slowly. 8. Wait at least 1 minute between puffs. 9. Replace the caps on the inhaler and the spacer. 10. At least once a day, clean the plastic case and cap of the inhaler by thoroughly rinsing in warm, running tap water; at least once a week, clean the spacer in the same manner. Without a Spacer 1. Before each use, remove the cap and shake the inhaler according to the instructions in the package insert. 2. Tilt your head back slightly and breathe out fully. 3. Open your mouth and place the mouthpiece 1 to 2 inches away. 4. As you begin to breathe in deeply through your mouth, press down firmly on the canister of the inhaler to release one dose of the drug. 5. Continue to breathe in slowly and deeply (usually over 5–7 seconds). 6. Hold your breath for at least 10 seconds to allow the drug to reach deep into the lungs and then breathe out slowly. 7. Wait at least 1 minute between puffs. 8. Replace the cap on the inhaler. 9. At least once a day, remove the canister and clean the plastic case and cap of the inhaler by thoroughly rinsing in warm, running tap water. 10. Avoid spraying in the direction of your eyes. FIG. 7.4 Patient using an aerosol (metered-dose inhaler) with a spacer. (From Ignatavicius D, Workman ML, Rebar C: Medical-surgical nursing, ed 9, St. Louis, 2018, Elsevier.) 231 FIG. 7.5 Example of a dry-powder inhaler with a counter. (Courtesy GlaxoSmithKline.) Box 7.2 Teaching a Patient How to Use a Dry-Powder Inhaler For Inhalers That Require Loading First load the drug by: • turning the device to the next dose of drug, or • inserting the capsule into the device, or • inserting the disk or compartment into the device. After Loading the Drug and for Inhalers That Do Not Require Drug Loading • Read your healthcare provider's instructions for how fast you should breathe for your particular inhaler. • Exhale fully away from the inhaler. • Place your lips over the mouthpiece and breathe in forcefully (there is no propellant in the inhaler; only your breath pulls the drug in). • Remove the inhaler from your mouth as soon as you have breathed in. • Never exhale (breathe out) into your inhaler. Your breath will moisten the powder, causing it to clump and not be delivered accurately. • Never wash or place the inhaler in water. • Never shake your inhaler. • Keep your inhaler in a dry place at room temperature. • If the inhaler is preloaded, discard it after it is empty. • The drug is a dry powder and there is no propellant, so you may not feel, smell, 232 or taste it as you inhale. Irritation of the lung passages, mouth, and throat may occur with use of powdered drug forms or other inhaled agents. Rinsing the mouth with water after each treatment helps reduce this problem. Evaluation. Check the patient's pulse and blood pressure, and compare these findings with the baseline findings to assess whether the heart is affected by the drug. Response to therapy varies among patients. Assess for rate, depth, and ease of respiration to determine whether breathing problems have improved. Patient and family teaching. Tell the patient and family the following: • Take the drug as directed by the healthcare provider and do not change the dose. • Overuse of these drugs may result in severe side effects. • Contact your healthcare provider if the drug is not helping your breathing problems. • Contact your healthcare provider if bronchial irritation, dizziness, chest pain, insomnia, or any changes in symptoms occur. • Drinking lots of flui