PH 9 Drugs Affecting the Renal Urinary and Cardiovascular Systems.pdf

8 Drugs Affecting the Renal/Urinary and Cardiovascular Systems LEARNING OUTCOMES 1. List the names, actions, possible side effects, and adverse effects of diuretic drugs. 2. Explain what to teach patients and families about diuretic drugs. 3. List the names, actions, possible side effects, and adve...

8 Drugs Affecting the Renal/Urinary and Cardiovascular Systems LEARNING OUTCOMES 1. List the names, actions, possible side effects, and adverse effects of diuretic drugs. 2. Explain what to teach patients and families about diuretic drugs. 3. List the names, actions, possible side effects, and adverse effects of drugs to treat benign prostatic hyperplasia and overactive bladder. 4. Explain what to teach patients and families about drugs to treat benign prostatic hyperplasia overactive bladder. 5. List the names, actions, possible side effects, and adverse effects of drugs for high blood cholesterol and drugs for high blood pressure. 6. Explain what to teach patients and families about drugs to treat high blood lipid levels and about drugs to treat high blood pressure. 7. List the names, actions, possible side effects, and adverse effects of drugs for angina and heart failure. 8. Explain what to teach patients and families about drugs to treat angina and heart failure. 9. List the names, actions, possible side effects, and adverse effects of drugs for dysrhythmias. 10. Explain what to teach patients and families about drugs to treat dysrhythmias. KEY TERMS adrenergics (ǎ-drǎ-NĚR-jǐks, p. 141) A category of drugs that affects nervous system control of various organs and tissues by activating or blocking receptors that respond to the body's natural adrenergic substances, epinephrine and norepinephrine. alpha1-adrenergic antagonist (ǎ-drǎ-NĚR-jǐk ǎn-TĂ-gě-nǐst, p. 144) A type of adrenergic drug that lowers blood pressure by blocking the adrenergic receptor sites in blood vessel smooth muscle that, when activated, cause vasoconstriction and raise blood pressure. alpha2-adrenergic agonist (ǎ-drǎ-NĚR-jǐk Ă-gǎ-nǐst, p. 144) A type of adrenergic drug that works centrally (in the brain) to turn on special alpha2 receptors that, when normally activated, actually cause vasodilation and decrease blood pressure. 243 angiotensin-converting enzyme inhibitor (ACE-I) (ǎn-jē-ō-TĚN(T)-sən kŭnˈVĚRT-ǐng ĚN-zīm ǐn-HĬ-bǎ-těrz, p. 139) A type of renin-angiotensinaldosterone system drug that reduces high blood pressure by stopping the conversion of angiotensin I to angiotensin II (the hormone that causes the vasoconstriction and increased aldosterone). angiotensin II receptor blocker (ARB) (ǎn-jē-ō-TĚN(T)-sən rǐ-SĚP-těr, p. 139) A type of renin-angiotensin-aldosterone system drug that actually blocks the vasoconstrictor and aldosterone-secreting effects of angiotensin II to lower blood pressure by selectively blocking the binding of angiotensin II at receptor sites found in many tissues. antidysrhythmic (ĂN-tī-dǐs-RĬTH-mǐk, p. 150) Drug that works to make heart rhythm more regular and reduce serious dysrhythmias. antihyperlipidemic (ĂN-tī-hī-pěr-lǐ-pǎ-DĒ-mǐk, p. 134) Drug that lowers blood lipid levels. antihypertensive (ĂN-tī-hī-pěr-TĚN(t)-sǐv, p. 139) Drug that has the main purpose of lowering blood pressure. beta blocker (BĀ-tǎ, p. 141) Drug that works as an antagonist and blocks the activity of beta-adrenergic receptors. Its main action lowers blood pressure and slows heart rate. calcium channel blockers (KĂL-sē-ěm, p. 141) A class of antihypertensive drugs that lower blood pressure by reducing the effect of calcium in the heart muscle and in the smooth muscles of arteries. diuretic (dī-yǎ-RĚ-tǐk, p. 126) Drug that has the main action of decreasing fluid volume by increasing urine output. hydroxymethylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors (statins) (rēDŬK-tās ǐn-HĬ-bǎ-těrz, p. 135) Antihyperlipidemic drugs that lower blood low-density lipoprotein levels by slowing liver production of cholesterol. inotropic drug (ǐ-nǎ-TRŌ-pǐk, p. 153) A drug that affects contractility of the myocardium. A positive inotropic drug increases contractility; a negative inotropic drug decreases contractility of the myocardium. loop diuretic (lūp dī-yǎ-RĚ-tǐk, p. 127) Drug that increases urine output by blocking active transport of chloride, sodium, and potassium in the thick ascending loop of Henle. nitrates (NĪ-trāts, p. 147) A class of drugs that relax (dilate) peripheral veins and reduce resistance to blood flow in the arteries. potassium-sparing diuretics (pǎ-TĂ-sē-ěm, p. 127) Drugs that increase the excretion of water and sodium through increased urine output without the loss of potassium in the urine. renin-angiotensin-aldosterone system (RAAS) drugs (RĚ-něn ǎn-jē-ō-TĚN(T)-sən ǎl-dō-STĚR-ōn, p. 140) Drugs that include angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers that have the effect of interfering with the action of angiotensin II and aldosterone. thiazides and thiazide-like sulfonamides diuretics (THĪ-ǎ-zīds, p. 126) Drugs that increase urine output by preventing water, sodium, potassium, and chloride 244 from being reabsorbed into the blood through the walls of the nephron. urinary antispasmodic (YŪR-ǎ-něr-ē ĂN-tī-spǎz-MĂ-dǐk, p. 132) Drug that reduces overactive bladder symptoms by relaxing the bladder muscle. vasodilators (vā-zō-DĪ-lā-těrs, p. 145) A class of drugs that act directly on the smooth muscle in the blood vessel walls to cause them to dilate (widen or relax). The renal/urinary system works together with the cardiovascular system to maintain adequate circulation to all parts of the body. The interactions between these two systems help to maintain fluid balance, delivery of nutrients, and removal of waste products from cells, tissues, and organs. Most drugs that affect one system have an effect on the functioning of the other system. Drugs That Affect the Renal/Urinary System The renal/urinary system consists of two kidneys, two ureters, the bladder, and the urethra (Fig. 8.1). The kidneys act as a filter for the blood that circulates throughout the cardiovascular system. The renal/urinary system (kidneys and bladder) controls how much blood is in the body and the content of the fluid portion of the blood because of its close connection with the cardiovascular system. Although the kidneys do not regulate what comes into the body, they balance all body fluids and the blood by carefully controlling which substances remain in the body versus which substances leave the body. In a sense, the kidneys act like a “washing machine” for the blood, removing wastes, excess substances, and extra fluid. Most drugs that affect the renal/urinary system change how much water and other substances are retained by the body or excreted in the urine. FIG. 8.1 The urinary system. (From Herlihy B: The human body in health and illness, ed 5, St. Louis, 2014, Elsevier.) 245 Diuretics Diuretics are drugs that have the main action of decreasing fluid volume by increasing urine output. Although their site of action is the kidney, diuretics are chiefly used for cardiovascular problems such as high blood pressure (HBP; hypertension) and heart failure, rather than for kidney problems. Diuretics typically work well, are safe, are well tolerated by the patient, and are generally cost-effective. Diuretics are usually classified into four groups: thiazides (e.g., chlorothiazide and hydrochlorothiazide), the thiazide-like sulfonamides (e.g., metolazone and indapamide), loop diuretics (e.g., furosemide and bumetanide), and the potassiumsparing diuretics (e.g., amiloride, triamterene, and spironolactone). The most effective diuretics are those that work at the ascending loop of Henle in the nephron (Fig. 8.2). FIG. 8.2 Sites of diuretic action on the kidney and nephron. (From Workman ML, LaCharity LA: Understanding pharmacology, ed 2, St. Louis, 2016, Elsevier.) Memory Jogger The four main categories of diuretics are: • thiazide diuretics • thiazide-like sulfonamide diuretics • loop diuretics • potassium-sparing diuretics 246 Actions Thiazides and thiazide-like sulfonamide diuretics work at the end of the ascending loop of Henle and the beginning of the distal convoluted tubule in the nephron (see Fig. 8.2). This class of drugs increases urine output by preventing water, sodium, potassium, and chloride from going through the walls of the nephron to be reabsorbed back into the blood. They are not reabsorbed, so the water and electrolytes stay within the tubules, making their way through the renal system into the bladder and then being excreted from the body. Thiazide and thiazide-like drugs are the most commonly used type of diuretic and often are first line in the management of HBP. Over the long term, thiazides also act to dilate the smooth muscles in the arterioles, the smallest vessels in the arterial system. The heart does not have to work so hard to pump blood into the vascular system because the arterioles are dilated. See Table 8.1 for the dosages and nursing implications of selected thiazide diuretics. Table 8.1 Common Diuretics Thiazides: These drugs work to lower blood pressure by increasing urine output by preventing water, sodium, potassium, and chloride from going through the walls of the nephron to be reabsorbed back into the blood. They also dilate arterioles by relaxing the smooth muscle in these blood vessel walls. DRUGS/ADULT DOSAGE RANGE NURSING IMPLICATIONS chlorothiazide (Diuril) 500–1000 mg orally • Weigh the patient daily while he or she is taking diuretics to monitor trends and prevent dehydration. once or twice daily • In the acute care setting, monitor intake and output to make sure that the patient achieves fluid balance. hydrochlorothiazide (Esidrix, Ezide, • Monitor potassium levels to assess that they are within normal levels because these drugs reduce blood Hydrodiuril, Oretic, Zide) 12.5–50 mg potassium levels. orally daily • Monitor the patient's basic metabolic panel (BMP) to check for abnormal electrolytes, blood urea nitrogen (BUN), and/or creatinine. These laboratory tests can indicate fluid and electrolyte imbalance or kidney problems. • Report potassium levels below normal to the healthcare provider because low potassium levels can have serious effects on muscles and breathing. • Inform the healthcare provider if your patient has a history of gout because thiazide diuretics can cause a flare-up. • If the patient has diabetes, monitor his or her glucose level carefully because diuretics can cause elevated blood sugar. • Hold diuretics if patients have a blood pressure less than 90/60 mm Hg because this can be a symptom of dehydration or other adverse effects. Thiazide-like sulfonamides: Like the thiazide diuretics, these drugs lower blood pressure by preventing water, sodium, potassium, and chloride from going through the walls of the nephron to be reabsorbed back into the blood. They also dilate arterioles by relaxing the smooth muscle in these blood vessel walls. DRUGS/ADULT DOSAGE RANGE NURSING IMPLICATIONS indapamide (Lozol) 1.25–2.5 mg orally • Weigh the patient daily while he or she is taking diuretics to monitor trends and prevent dehydration. daily • Monitor potassium levels to assess that they are within normal levels because these drugs reduce blood metolazone (Zaroxolyn) 2.5–5 mg orally potassium levels. daily • Report potassium levels less than 3.5 mEq/L or 3.5 mmol/L to the healthcare provider because low potassium levels can have serious effects on heart rhythm. Loop diuretics: Loop diuretics work to increase urine output by blocking active transport of chloride, sodium, and potassium in the thick ascending loop of Henle. DRUGS/ADULT DOSAGE RANGE NURSING IMPLICATIONS bumetanide (Bumex) 0.5–2 mg orally. 0.5– • Side effects are more severe with loop diuretics than other diuretics because drugs in this class are the most 1.0 mg IM to maximum of 10 mg per powerful diuretics. day • Watch for symptoms of low potassium including dry mouth, increased thirst, muscle cramps, fatigue, furosemide (Delone, Lasix) 20–120 mg weakness, and mood changes, because low potassium levels can have serious effects on muscles and orally daily; 20–40 mg IM breathing. • Report potassium levels less than 3.5 mEq/L or 3.5 mmol/L to the healthcare provider because low potassium levels can have serious effects on heart rhythm. • Remind the patient to stand up slowly to avoid orthostatic hypotension. • Notify the healthcare provider if the patient reports decreased hearing or a ringing in the ears because loop diuretics can be ototoxic (can damage hearing). Discontinuing the drug typically reverses the changes in hearing. • Monitor blood glucose in patients with diabetes because these drugs can cause hyperglycemia. • Check and record urine output to make sure the drug is working properly. You may need to empty the Foley catheter more frequently. • Urination typically occurs within 1 hour, so inform the patient that he or she will need to be close to a bathroom to avoid urinary urgency or incontinence. Potassium-sparing diuretics: These drugs increase the excretion of water and sodium, leading to increased urine output without the loss of potassium. They act by slowing the sodium pump in the distal tubule of the nephron so more sodium and water is excreted as urine. DRUGS/ADULT DOSAGE RANGE NURSING IMPLICATIONS amiloride (Midamor) 5–10 mg orally daily • Monitor potassium levels to assess whether they are within normal levels because higher-than-normal spironolactone (Aldactone) 50–100 mg blood potassium levels can occur with these drugs. orally once or in divided doses • Report potassium levels greater than 5.0 mEq/L or 5.0 mmol/L to the healthcare provider because high 247 triamterene (Dyrenium) 50–100 mg twice daily potassium levels can cause dangerous cardiac problems. • Teach patients signs of a high potassium level, including confusion, irregular heartbeat, nervousness, numbness or tingling in the hands or feet, unusual fatigue, and a heavy feeling in the legs. • Teach patients to stand up slowly to avoid orthostatic hypotension because these drugs decrease fluid volume and decrease blood pressure. • Teach the patient to avoid foods high in potassium (see Box 8.1) to prevent hyperkalemia. • Remind patients to avoid salt substitutes because they are often high in potassium. Lifespan Considerations Pregnancy and Breast-Feeding Thiazide diuretics are approved for use during pregnancy and may be used in low doses for breast-feeding mothers without adverse effects on the infant. More powerful diuretics are usually not recommended during pregnancy unless essential for the mother's health. High doses of diuretics for breast-feeding women may suppress lactation. Loop diuretics are drugs that increase urine output by blocking active transport of chloride, sodium, and potassium in the thick ascending loop of Henle (see Fig. 8.2). Loop diuretics are widely considered the most powerful of the diuretics. Use can result in significant decreases in fluid volume and increase in urine output. Loop diuretics are used in a variety of conditions including heart failure, pulmonary edema, and cirrhosis of the liver with ascites. Potassium is one of the major electrolytes that can be lost after loop diuretic administration. Therefore monitor potassium levels carefully because significant changes in potassium can result in cardiac dysrhythmias. See Table 8.1 for the dosages and nursing implications of selected loop diuretics. Memory Jogger Water always follows sodium. Diuretics that work by increasing sodium excretion in the urine always increase the water in urine output. Potassium-sparing diuretics increase the excretion of water and sodium, leading to increased urine output without the loss of potassium. They are called potassiumsparing because they do not “waste” potassium, which often occurs with thiazide and loop diuretics. Potassium-sparing diuretics act by slowing the sodium pump in the collecting duct of the nephron so that more sodium and water are excreted as urine (see Fig. 8.2). See Table 8.1 for the dosages and nursing implications of selected potassium-sparing diuretics. Lifespan Considerations Older Adults: Diuretics 248 Older adult patients are more likely to develop postural hypotension, confusion, low potassium levels (hypokalemia) (except with potassium-sparing diuretics), and increased serum glucose levels when on diuretics. Lower dosages may be required based on patient responses. Monitor older adults on diuretics more frequently for dehydration and symptoms of low potassium levels (hypokalemia), such as muscle weakness and irregular heartbeats. Uses Healthcare providers prescribe diuretics for a variety of conditions including HBP, heart failure, and cirrhosis of the liver. They are typically used in conditions that require a decrease in edema (decrease in fluid volume). Diuretics can sometimes increase the excretion of other drugs in cases of overdose (such as aspirin). Expected Side Effects Common side effects of diuretics include urinary urgency and urinary frequency. Other expected side effects include dry mouth, increased thirst, and lightheadedness. Fluid and electrolyte imbalances are a common side effect of diuretics. Thiazide diuretics can cause an increase in uric acid, which can cause flare-ups of gout in certain patients. See Table 8.1 for specific dosages and nursing implications associated with each specific class of diuretics. Adverse Effects Diuretics increase urine output, so dehydration is one of the major adverse effects. Signs and symptoms of dehydration include increased heart rate, low blood pressure, decreased urine output or dark yellow urine, dry mouth with a sticky coating on the tongue, and tenting of the chest or the forehead (if you pinch the skin, the skin remains like a tent when you release the skin). Thiazides and loop diuretics can cause severe hypokalemia (low potassium), whereas potassium-sparing diuretics can cause hyperkalemia (high potassium). Signs of hypokalemia include muscle cramping, abnormal heart rhythm, and changes in reflexes. Signs of hyperkalemia include confusion, irregular heartbeat, numbness of the hands or feet, and a feeling of heaviness in the legs. Loss of sodium can cause confusion, irritability, fatigue, and even seizures in some patients. A major adverse effect of all diuretics is severe low blood pressure that can result in falls, particularly in high-risk and older patients. Drug Interactions Increased loss of potassium can result from use of thiazide or loop diuretics if the patient is taking corticosteroids or certain antibiotics. For patients with bipolar illness using lithium, the loss of sodium caused by diuretics can increase the risk for lithium toxicity. Potassium-sparing diuretics with angiotensin-converting enzyme inhibitors (ACE-Is) or angiotensin receptor blockers (ARBs) can lead to hyperkalemia. Patients taking potassium-sparing diuretics should avoid salt substitutes to decrease the risk for hyperkalemia. 249 Top Tip for Safety Potassium levels that are too high or too low can cause life-threatening dysrhythmias. Nursing Implications and Patient Teaching Assessment. Make sure to assess the patient for changes in vital signs (particularly a decrease in blood pressure). Assess the patient carefully for any signs of dehydration before giving any diuretic. Monitor daily weight for changes from a baseline weight (the patient's normal weight). If the patient's weight is below his or her normal weight, contact the healthcare provider before giving the diuretic. Check the patient's most recent potassium level. If the level is below the normal range (can be caused by thiazide or loop diuretics) or above the normal range (can be caused by potassiumsparing diuretics), make sure to contact the healthcare provider before you give the drug. Planning and implementation. Give the diuretics in the morning to avoid disturbing the patient's sleep at night. Be sure to tell patients that they will most likely experience urinary frequency and urgency, and thus should be near a bathroom or have access to a urinal or bedside commode after taking the drug. Also, make sure that they know to ask for help when getting up if needed. Tell patients to notify you if they have any weakness, muscle cramping, numbness or tingling in the extremities, or sensation of irregular heartbeat because these may be symptoms of a decrease in potassium level. Continue to monitor trends in daily weight and blood pressure while the patient is taking diuretics. For thiazides and loop diuretics, teach patient to eat foods high in potassium (Box 8.1). For patients taking potassium-sparing diuretics, teach patients to avoid foods high in potassium (see Box 8.1). Box 8.1 Sources of High and Very High Potassium Foods CATEGORY HIGH (200–300 MG/SERVING) VERY HIGH (>300 MG/SERVING) Fruits Apricots (canned) Oranges (1 medium) Orange juice Bananas, 1 small Mango, 1 medium Dried fruits, cup Peaches, fresh, 1 medium Asparagus, 4 spears Prune juice Beet greens, Beets, fresh or cooked Black beans, cooked ( Brussel sprouts Potatoes with skin, baked potato, Okra Baby carrots (10 pieces) Sweet potatoes, yams Bouillon, low sodium, 1 cup Milk, chocolate, 1 cup Pizza, 2 slices Salt substitute, teaspoon Vegetables Miscellaneous Peanut butter, 2 tablespoons Nuts and seeds, 1 ounce Chocolate, 1.5 ounce bar Salmon, canned, 3 ounces cup Yogurt, 6 ounce Milkshake, 1 cup 250 cup) medium Cappuccino, 1 cup Modified from Mahan, L. Kathleen, Raymond, Janice: Krause's food & the nutrition care process, 14th ed. Elsevier, St. Louis (2017); also used list from USDA Food Composition Database https://ndb.nal.usda.gov/ndb/search/list Patient and family teaching. Tell the patient and family the following: • Take the drug exactly as prescribed. Do not skip or double doses. • Doses are best taken early in the day to avoid affecting sleep at night. • If you are taking a thiazide or loop diuretics, include several high-potassium foods in the diet every day. • If you are taking a potassium-sparing diuretic, avoid foods high in potassium. • Use sunscreen and protective clothing to avoid skin irritation and sunburn because of photosensitivity. • Report any signs of abnormal potassium levels such as muscle cramping, weakness, numbness or tingling in the extremities, or sensation of irregular heartbeat to your healthcare provider. • Daily weight will be helpful to monitor if there is any change in fluid levels above or below your normal weight. Notify your healthcare provider if you experience any unintentional weight loss or weight gain. • If you are taking a diuretic for your blood pressure, remember that HBP is not cured by drugs, so do not stop taking the drug without consulting a healthcare provider. • Avoid taking any over-the-counter (OTC) drugs without discussing with your healthcare provider to avoid a drug interaction. Drugs for Benign Prostatic Hyperplasia Benign prostatic hyperplasia (BPH) is a noncancerous growth of the prostate gland frequently seen as men age. When the prostate gland becomes large enough, the patient can have problems urinating because the prostate puts pressure on the 251 bladder and urethra (Fig. 8.3). Drugs used in the management of BPH are the alpha1adrenergic receptor blockers that relax the smooth muscle of the prostate and bladder outlet and the testosterone inhibitors that shrink the prostate. Both types of drug can help the patient pass urine more easily. See Table 8.2 for the dosages and nursing implications of selected drugs to treat BPH. FIG. 8.3 (A) Normal prostate gland. (B) Enlarged prostate gland showing the narrowing of the urethra, decreasing urine flow. (From Workman ML, LaCharity LA: Understanding pharmacology, ed 2, St. Louis, 2016, Elsevier.) Table 8.2 Common Drugs for Benign Prostatic Hyperplasia Dihydrotestosterone (DHT) inhibitors: These drugs shrink the prostate by working as a “counterfeit” drug that looks like testosterone and binds to the enzyme that normally converts testosterone to DHT, its most powerful form. With less DHT in the prostate, the cells do not receive the signal to grow. As a result, the gland shrinks and puts less pressure on the urethra, allowing better urine flow. DRUGS/ADULT DOSAGE RANGE NURSING IMPLICATIONS dutasteride (Avodart) 0.5 mg orally • Teach patients that the most common side effect of these drugs is a decreased interest in sexual activity because once daily knowing about the side effects reduces anxiety when they appear. finasteride (Proscar, Propecia) 5 mg • Instruct patients to report breast enlargement, nipple drainage, or pain in the testicles to their healthcare orally once daily provider because these drugs may affect other hormones and sex tissues. • Warn patients and family members that pregnant women should not handle or touch these drugs because they can cause birth defects when absorbed through the skin. • Teach men who are having sex with a pregnant woman to wear a condom to prevent exposure to the fetus because this drug is present in seminal fluid. Selective alpha1 blockers: Relax smooth muscle tissue in the prostate gland, the neck of the bladder, and the urethra by binding to the alpha1-adrenergic receptors in these tissues. When the receptors are activated, the smooth muscle constricts, tightening the prostate, which increases the pressure and squeezes the urethra. When these receptors are bound with selective alpha1 blockers, the smooth muscle relaxes, placing less pressure on the urethra and improving urine flow. DRUGS/ADULT DOSAGE RANGE NURSING IMPLICATIONS alfuzosin (Uroxatral) 10 mg orally • Ask patients who are taking tamsulosin whether they have an allergy to sulfa drugs because tamsulosin is once daily made from a sulfonamide and may cause an allergic reaction in patients who are allergic to sulfa drugs. silodosin (Rapaflo) 8 mg orally once • Teach patients that the most common side effect of these drugs is a decreased interest in sexual activity because daily knowing about the side effects reduces anxiety when they appear. tamsulosin (Flomax) 0.4–0.8 mg orally • Warn patients to change positions slowly because these drugs lower blood pressure and can cause dizziness. once daily 30 minutes after a meal terazosin (Hytrin) 1—10 mg orally once daily at bedtime Bladder Anesthetics Bladder anesthetics are drugs that, when taken orally, are excreted into the urine and act as a local anesthetic on the mucous membranes of the urinary tract. The only drug in this class is phenazopyridine. Phenazopyridine can control symptoms of 252 urinary irritation including burning, pain, and urinary frequency that often results from an acute urinary tract infection (like an “aspirin for the bladder”). The usual adult dosage is 200 mg orally three times daily after meals for 2 days. Warn patients that this drug turns the urine an orange-red color that can stain the toilet and clothing. Phenazopyridine does not treat the cause of the irritation to the bladder. It is not an antibiotic and cannot cure a urinary tract infection when used alone. Top Tip for Safety Phenazopyridine can be used a maximum of 2 days. If the patient is still having symptoms of bladder irritation after 2 days, notify the healthcare provider. Drugs for Overactive Bladder An overactive bladder (OAB) is a problem in which the person has a sudden, urgent need to urinate. In OAB, the detrusor muscle (bladder wall muscle) contracts before the bladder is full (Fig. 8.4). Often the person with OAB feels an urgent need to urinate (urgency) and may lose bladder control before reaching a toilet (urinary incontinence). Although OAB can occur in men and women, the problem is more common in women. Prevalence increases with age and can significantly affect quality of life. FIG. 8.4 Pathophysiology of overactive bladder. (From Workman ML, LaCharity LA: Understanding pharmacology, ed 2, St. Louis, 2016, Elsevier.) 253 Drugs prescribed for OAB are urinary antispasmodics, which improve symptoms and reduce incontinence by decreasing bladder muscle spasms. See Table 8.3 for the dosages and nursing implications of selected urinary antispasmodics. Table 8.3 Common Drugs for Overactive Bladder Urinary antispasmodics: inhibit involuntary nerve-induced contractions of the detrusor muscle in the bladder wall, allowing the bladder to relax and hold more urine without the strong urge to urinate. DRUGS/ADULT DOSAGE RANGE NURSING IMPLICATIONS oxybutynin (Ditropan) 5 mg orally two to three • Tell patients that common side effects include dry mouth, dry eyes, headache, and constipation times daily because knowing the expected side effects reduces anxiety. oxybutynin (Ditropan XL) 5 mg orally once daily • Teach patients to check their heart rates at least once daily and report irregularities or chest pain oxybutynin transdermal patch (Oxytrol) 3.9 mg/day because these are symptoms of an adverse reaction. applied transdermally every 3–4 days • Remind patients to avoid taking antihistamines with these drugs because the combination can tolterodine (Detrol) 2 mg orally twice daily cause urinary retention and/or constipation. tolterodine (Detrol LA) 4 mg orally once daily • Teach patients to weigh themselves and report weight gain (more than 2 lb/day) or increased solifenacin (Vesicare) 5–10 mg orally once daily swelling to the prescriber because these drugs can cause urinary retention and heart failure. darifenacin (Enablex) 7.5–15 mg orally once daily • Remind patients to avoid becoming overheated or dehydrated during exercise or hot weather trospium chloride (Sanctura) 20 mg orally twice because these drugs decrease sweating and increase the risk for heatstroke. daily 1 hour before meals or on an empty stomach • Teach patients to avoid consuming alcohol within 2 hours of these drugs because side effects such trospium chloride (Sanctura XR) 60 mg once daily 1 as drowsiness are increased. hour before breakfast • Teach patients to avoid driving or any other activities that require clear vision until they know how the drugs will affect them because this class of drugs can cause blurred vision. • Teach patients using the transdermal patch system to remove the old patch before applying a new one to prevent drug overdoses. Drugs That Affect the Cardiovascular System The primary purpose of the cardiovascular system is to supply oxygenated blood that includes water (plasma), nutrients, and hormones to tissues and organs, and remove carbon dioxide and waste products for elimination. Any breakdown in cardiovascular functioning can lead to uncomfortable symptoms, decreased quality of life, and even death if not managed carefully. The cardiovascular system consists of the heart and blood vessels working together to move blood throughout the body. Using specialized cardiac muscle and nerve systems, electrical impulses cause the heart muscle to contract, pumping blood from the heart into the aorta to the arteries (Fig. 8.5). The oxygenated blood moves through the arteries to the arterioles, then to capillaries, where oxygen exchanges with carbon dioxide. The deoxygenated blood moves from the capillaries to the venules, then to the larger veins and back into the vena cava, where it returns to the heart. 254 FIG. 8.5 (A) Using specialized cardiac muscle and nerve systems, electrical impulses cause the heart muscle to contract. (B) This results in blood pumping from the heart into the aorta to the arteries. (From Workman ML, LaCharity LA: Understanding pharmacology, ed 2, St. Louis, 2016, Elsevier.) Healthcare providers use a variety of approaches to prevent symptoms, manage symptoms, or treat abnormalities in the cardiovascular system. Some “cardiovascular” drugs help to prevent high cholesterol levels from narrowing arteries, others to treat HBP, and still others to manage symptoms associated with diseases of the heart itself. We will address some of the most common cardiovascular drugs that you might see in practice to give you the best overview of how these drugs can help provide the 255 best health and quality of life possible for your patients. As we do this, we will proceed from drugs typically used to reduce risk for cardiovascular disease to those drugs that treat cardiovascular disease. Two major risk factors for cardiovascular disease are high levels of blood lipids (hyperlipidemia) and HBP (hypertension). Effective drug therapy can modify both of these risk factors. High levels of blood lipids, including cholesterol, can lead to thickening of the lining of arteries with fatty plaque, a condition called atherosclerosis (Fig. 8.6). Eventually atherosclerosis blocks some blood flow through the arteries. In combination with HBP, greater amounts of plaque occur with further blood vessel narrowing. As a result, the heart has to work harder to pump blood through the narrowed blood vessels. FIG. 8.6 (A) Normal blood flow through the artery. (B) Artery obstructed by atherosclerotic plaque. Note the restricted blood flow through the artery. (From Workman ML, LaCharity LA: Understanding pharmacology, ed 2, St. Louis, 2016, Elsevier.) Decreased blood flow through the coronary arteries that supply the heart muscle with oxygen can result in ischemia (lack of oxygen to the tissue) and pain called angina. To treat angina, select cardiovascular drugs can dilate (widen) the coronary arteries, thereby getting blood and oxygen to the heart muscle. If the blood flow is severely impaired through the coronary arteries or if a clot forms in a coronary artery, the patient can experience a myocardial infarction (heart attack) that results from a severe lack of oxygen to the heart muscle. Over time, the ability of the heart to pump decreases in patients with prolonged HBP and/or changes in heart muscle resulting from a myocardial infarction. The decreased ability of the heart to pump effectively is called heart failure. Heart failure is managed by using a variety of cardiovascular drugs to improve the ability of the heart to pump and reduce the associated symptoms. An additional result of damage to the heart muscle from HBP and atherosclerosis is changes within electrical conduction system of the heart. These changes can result 256 in dysrhythmias (abnormal heart rhythms). The dysrhythmias can cause significant decreases in cardiac output and even death if not managed effectively. A number of cardiovascular drugs are used to restore normal heart rhythms. In summary, the cardiovascular drug groups that we will discuss in this chapter include cholesterol-lowering drugs, blood pressure–lowering drugs, blood vessel dilators (antianginals), drugs to improve heart muscle contraction (positive inotropic drugs), and drugs to make electrical conduction through the heart more regular (antidysrhythmics). At times a patient may be taking drugs from a variety of cardiovascular drug categories. Memory Jogger The most common types of cardiovascular drugs are: • antihyperlipidemics • antihypertensives • drugs for angina • drugs for heart failure • antidysrhythmics Antihyperlipidemics Hyperlipidemia is the condition of high levels of lipids, primarily cholesterol, and other fatty acids in the blood. Antihyperlipidemics are drugs that lower blood cholesterol levels. The body needs a certain amount of cholesterol for healthy cell membranes, hormones, vitamin D, and bile acids, so it is a normal and vital part of blood plasma. The liver produces much of the body's cholesterol. Therefore when you think about cholesterol levels, you need to recognize that the levels are a combination of the cholesterol ingested in the diet and the cholesterol produced by the liver. It is important to note, though, that the liver contributes much more cholesterol to blood cholesterol levels than does the food you eat. Blood lipids (cholesterol and other fatty acids) move through the body attached to protein carriers called lipoproteins. When considering cardiovascular disease and atherosclerosis, the most important lipoproteins are the high-density lipoproteins (HDLs), which are protective, and low-density lipoproteins (LDLs), which are harmful. As you think about drugs for reducing cholesterol, you can consider the effect of the drug on the “good” cholesterol (the protective HDLs) or on the “bad” cholesterol (the harmful LDLs). HDLs remove cholesterol from the blood and transport it to the liver. If you have ever seen a catfish in action, you can see that it acts as a “scavenger” for food and cleans up the bottom of the fish tank. HDLs scavenge harmful lipids from the blood so that it does not stick to blood vessels and contribute to plaque. On the other hand, LDL cholesterols are major contributors to the onset and progression of heart disease and stroke. For some patients, lipid levels are improved through diet, exercise, and lifestyle changes. Others may require lipid-lowering drugs (antihyperlipidemics). Most lipid- 257 lowering drugs tend to reduce LDLs and other fatty acids. Some drugs can actually increase the scavenger HDLs. Memory Jogger LDLs are the “bad” cholesterol; HDLs are the “good” cholesterol. Five classes of drugs are used to treat hyperlipidemia: statins (HMG-CoA [hydroxymethylglutaryl coenzyme A] reductase inhibitors), selective cholesterol absorption inhibitors, fibric acid derivatives, bile acid sequestrants, and niacin or nicotinic acid. Memory Jogger The five classes of antihyperlipidemics are: • HMG-CoA reductase inhibitors (most common) • cholesterol absorption inhibitors • fibric acid derivatives (fibrates) • bile sequestrants • niacin or nicotinic acid HMG-Coa Reductase Inhibitors (Statins) Actions HMG-CoA reductase inhibitors (also called “statins”) are antihyperlipidemic drugs that lower blood LDL levels by slowing cholesterol production by the liver. They do not remove dietary cholesterol from the blood. The statins are the most effective drugs for lowering LDL levels and raising HDL levels. See Table 8.4 for the dosages and nursing implications of commonly prescribed HMG-CoA reductase inhibitors. Be sure to consult a drug reference source or handbook for information on other statin drugs. Table 8.4 Common HMG-CoA Reductase Inhibitors (Statins) Drugs HMG-CoA reductase inhibitors (statins): antihyperlipidemic drugs that lower blood LDL levels by slowing liver production of cholesterol. They do not remove dietary cholesterol from the blood. DRUGS/ADULT DOSAGE NURSING IMPLICATIONS RANGE atorvastatin (Lipitor) 10–80 mg • Remind patients to remain on a low-cholesterol diet while taking statins because drugs do not reverse a highorally once daily cholesterol diet. fluvastatin (Lescol) 20–40 mg • Check drug references for individual statins because some have best effects when taken in the evening and others can orally once or twice daily be taken without regard to meals for best effect. fluvastatin extended release • Teach patients to avoid alcohol because drinking alcohol puts stress on the liver and adds to the stress of these drugs. (Lescol XL) 80 mg orally once • Tell patients to report severe muscle aches, changes in urine color, or decreased urine output because statins can daily cause rhabdomyolysis, a disorder resulting from broken muscle cells that damage the kidneys. lovastatin (Altoprev) 20–80 mg • Teach patients that they should avoid grapefruit juice because it interacts with statins and can cause drug toxicity. orally once daily with evening • Remind patients to follow up with their healthcare provider for regular laboratory work because statins can cause meal liver problems. lovastatin extended release • Monitor patients for signs of liver problems, such as nausea, yellowing of the eyes or roof of the mouth, darkened 258 (Altoprev) 20–60 mg orally urine, or light-colored stools, because these symptoms suggest damage to the liver. once daily with evening meal • Side effects are rare, but some patients experience GI symptoms including upset stomach, gas, constipation, and pravastatin (Pravachol) 10–80 stomach cramps. Some patients experience mild muscle or joint ache. If patients experience these symptoms, remind mg orally once daily them to contact their healthcare provider rather than stopping the drug. rosuvastatin (Crestor) 5–40 mg orally once daily simvastatin (Zocor, FloLipid) 5– 40 mg orally once daily in the evening Uses The main use of statins is to lower blood LDL levels to reduce the risk for atherosclerosis, hypertension, heart attack, peripheral arterial disease, and stroke. Although other benefits have been described for statins, they are approved only to lower blood cholesterol levels. Expected Side Effects The most common side effects of statins include abdominal pain, headache, diarrhea, and muscle and joint discomfort. Other side effects are sore throat and heartburn. Patients with diabetes may experience an elevation of blood glucose. There is some evidence that long-term use of statins may be associated with cataract formation; however, the benefit of statin use outweighs the risk for cataracts. Adverse Effects The action of statins is in the liver and thus liver function is affected to some degree. Although rare, liver failure has been reported. With higher doses of statins patients may experience rhabdomyolysis (muscle breakdown). This is a very serious condition that can be life-threatening. Signs and symptoms of rhabdomyolysis include general muscle soreness, muscle pain, muscle weakness, stomach pain, and brown (teacolored) urine. The brown urine results from the kidneys trying to filter out the products of muscle breakdown. Ultimately the patient experiences kidney failure. Statins are dangerous if used during pregnancy. Cholesterol is important for normal brain development. If taken during pregnancy, statins can lower the cholesterol levels in the fetus, which results in brain deformities. For the same reason, statins are contraindicated in women who are breast-feeding. Lifespan Considerations Pregnancy and Breast-Feeding Statins are contraindicated during pregnancy and breast-feeding because of the effects of lower cholesterol levels on the developing brain. Drug Interactions Alcohol and acetaminophen increase the liver toxicity effects of statins. Aspirin and antacids decrease the effectiveness of statins. Grapefruit juice can increase the concentration of statins in the blood and should be avoided to reduce the risk for toxic side effects. 259 Nursing Implications and Patient Teaching Assessment. Carefully assess the patient's dietary patterns. Even though the patient is taking a drug to decrease cholesterol, it is not a good reason to continue eating foods high in saturated fats, such as fatty meats, fried foods, and baked goods made with trans fats such as donuts or cookies. Review liver function tests in the medical record before giving statins. If you see any abnormalities or have any questions, contact the registered nurse (RN) or the healthcare provider. If you are working in a community setting, it will be important to know if women are pregnant or planning pregnancy because statins are very dangerous to the fetus. Furthermore, women must avoid statins while breastfeeding. In other adults, assess for any symptoms of impaired liver function. Ask patients about their use of alcohol before starting statin therapy. Heavy use of alcohol contributes to liver problems while taking statins, so the patient will need to understand this before he or she begins therapy. Planning and implementation. While on statin therapy patients may have scheduled blood lipid levels ordered by the prescriber. Patients will need to fast at least 12 hours before having cholesterol, HDL, LDL, and triglyceride levels drawn. Timing of statin administration is very important to obtain the best result. A pharmacist or drug reference is helpful in determining the best time to give a specific statin. Some statins work best when given in the evening, some can be taken once a day without regard to meals, and some may need to be taken twice a day. Do not give the drug with grapefruit juice because this juice inhibits drug breakdown, allowing higher drug blood levels that can cause toxic side effects. Evaluation. Monitor for expected side effects, including headache, upset stomach, sore throat, or diarrhea. These side effects are typically short-term and go away after time. Check patient for jaundice (yellowing of the skin and mucous membranes including whites of the eyes), as well as darkening of the urine or clay-colored stools. These are indications of liver toxicity (hepatotoxicity). All patients taking statins usually have regular liver function studies after starting the drug and then yearly or whenever symptoms occur. If the patient has any severe muscle aches or signs of liver problems, report these to the RN or healthcare provider immediately. Top Tip for Safety For patients who are taking statins, immediately report to the healthcare provider any severe muscle ache or signs of liver problems, such as jaundice or dark urine that the patient has noticed, because those symptoms can be signs of serious adverse effects. Patient and family teaching. 260 Tell the patient and family the following: • Lifestyle changes like exercise, a low-cholesterol diet, and good weight management are just as important while you are taking the statins to help prevent cardiovascular disease. • Make note of the recommended best time of day to take your statin and take it at the same time each day. • Inform your healthcare provider if you might be pregnant or plan to become pregnant because statins can cause birth defects. • Avoid grapefruit juice when you are taking statins because this can cause the drug to accumulate in the blood and increase the risk for toxic effects. • If you have any signs of liver problems such as lightcolored bowel movements, yellowish tinge to the skin or eyes, or dark urine, notify your healthcare provider immediately because these are indications of adverse drug effects. • If you have severe muscle aches, notify your healthcare provider because this is an indication of a possible adverse drug effect. • Expected side effects include headache, upset stomach, and mild achiness. These usually get better after a few weeks of starting the statin. • Websites like the American Heart Association (http://www.heart.org) have resources to help you learn about cholesterol and low-cholesterol diets. Nonstatin Antihyperlipidemic Drugs Nonstatin antihyperlipidemic drugs use a variety of actions to reduce blood cholesterol levels derived from ingested food. These drugs are used less often because they are not as effective as statins. They would most likely be prescribed if the person is not responsive to or unable to tolerate statins. Selective Cholesterol Absorption Inhibitors Selective cholesterol absorption inhibitors are the next most common drugs 261 prescribed for lowering cholesterol. Ezetimibe was the first agent introduced in this category. The drug stays in the intestinal wall and acts on the intestinal epithelial cells to limit the absorption of cholesterol from food and from other sources in the body. Selective cholesterol absorption inhibitors are often combined with statins in pill form to give the patient the best chance of lowering LDL cholesterol and raising HDL cholesterol. Fibric Acid Derivatives (Fibrates) Gemfibrozil and fenofibrate are the preferred drugs of the fibric acid derivatives because they are more effective and have fewer adverse effects compared with some other drugs. Both are highly effective at lowering triglycerides and increasing HDL levels, but they have little effect on lowering LDL levels. Gemfibrozil and fenofibrate are generally well tolerated but can cause liver toxicity and cholelithiasis (gallstones). In general, these drugs are not recommended for patients with a history of gallbladder disease. Bile Acid Sequestrants Bile acid sequestrants, such as cholestyramine and colestipol, increase excretion of cholesterol and reduce LDL levels. They do this by forming a solid compound with bile salts, which increases bile loss through the feces (stool). Normal fat digestion is disturbed, so many patients do not tolerate these drugs because of uncomfortable GI side effects (e.g., constipation, bloating, and nausea). Bile acid sequestrants are not absorbed, so they do not have some of the severe systemic adverse effects that other antihyperlipidemics have. Other drugs taken with the bile acid sequestrants may not get absorbed because they act by binding to substances in the intestinal tract. In particular, bile acid sequestrants reduce absorption of fat-soluble vitamins (A, D, E, and K), so the patient may show symptoms of vitamin deficiency especially if taking a high dose or the drugs are taken for a long time. Watch especially for bleeding problems that may result from vitamin K deficiency that affects the clotting cycle. Niacin or Nicotinic Acid You may have heard of niacin as one of the B-complex vitamins found in animal proteins, green vegetables, and whole wheat. In higher doses, it also can lower total cholesterol and LDLs, and can increase HDLs. Although recent guidelines suggest that niacin is not as effective as statins in reducing cardiovascular risk, you may see patients in your clinical practice who are taking niacin. One of the main problems with niacin use is the expected side effect of flushing (a sensation of warmth or “prickly heat” with redness that usually occurs on the face, neck, or trunk). The flushing occurs shortly after taking the drug and is very uncomfortable. Taking aspirin (30 minutes before) and increasing the niacin dosage very slowly over 3 to 4 weeks from 500 to 1000 mg three times daily may reduce the flushing. In addition, flushing may decrease over time while taking the drug. Other side effects include indigestion, gas, hot flashes, rapid heart rate, and sweating. Nursing Implications and Patient Teaching 262 Assessment. Just as with the statins, it is very important to assess the patient's diet history, including his or her ability to adhere to lifestyle recommendations. These are just as important as the drug therapy because no cholesterol-reducing drug cures hyperlipidemia. Assess the patient's liver function tests; if there are any abnormal results, notify the RN or the healthcare provider. Assess the patient's use of alcohol because alcohol can increase the risk for damage to the liver. Planning and implementation. For those nonstatin antihyperlipidemic drugs that affect absorption of cholesterol from the GI tract, you will likely be giving supplemental doses of vitamins A, D, and K. Just as for the statins, carefully review the proper timing of these drugs in relation to meals. By themselves, selective cholesterol absorption inhibitors can be given without regard to meals. However, they are often combined with statins, so timing would be similar to statin drugs. For best results, fibric acid derivatives like gemfibrozil should be given 30 minutes before the morning and evening meals. Bile acid sequestrants are usually taken one or two times a day before meals. The drugs come in powder form and must be mixed with water, milk, or juice. Monitor how well the patient is tolerating the drug. If there are any signs of severe GI symptoms such as abdominal pain, severe bloating, or severe constipation, notify the RN or the healthcare provider. Evaluation. The healthcare provider will order follow-up blood tests to determine the patient's responses to cholesterol-lowering therapy. Compare these test results with those obtained before the drug was started to evaluate drug effectiveness and any changes in liver function. Patient and family teaching. Tell the patient and family the following: • Take the drug at the time prescribed because timing is important for cholesterol-lowering drugs. • Notify your healthcare provider and your pharmacist that you are taking a cholesterol-lowering drug so that they carefully review drug interactions with other drugs you are taking. • Notify your healthcare provider if you have any significant side effects before you consider stopping the drug. Dosages may be adjusted by your healthcare provider or you may be switched to a different drug. • Your drugs do not cure your high cholesterol problem. Continue making healthy lifestyle choices. 263 Bookmark This! The American Heart Association has great information for you and your patients about heart health and heart disease: http://www.heart.org/HEARTORG. Antihypertensive Drugs Blood pressure is the pressure of circulating blood on the walls of arteries and veins as the blood moves through the body with each contraction and relaxation of the heart. A healthy blood pressure maintains circulation to major organs and all parts of the body during rest and during activity. Blood pressure that is too high or too low can cause critical problems that affect blood vessels, organs, and tissues. Many things can affect the blood pressure, including heart rate, how well the heart contracts, certain hormones, blood volume, physical activity, and stress. Hypertension (high blood pressure) is a disorder in which the patient's blood pressure is consistently elevated above normal values. If left untreated, hypertension will damage major organs including the heart, brain, and kidneys. Managing hypertension dramatically reduces the odds of heart attack, stroke, and kidney failure. There are two kinds of hypertension. In primary hypertension, the specific cause is unknown. In secondary hypertension, the blood pressure changes are a result of a specific cause. If the cause is treated or managed, the blood pressure naturally returns to normal. Most cases (about 90%) are primary hypertension. Primary hypertension cannot be cured but can be well managed with good drug therapy. We will focus our attention on managing primary hypertension. Even though hypertension is the technical term, we will use the phrase high blood pressure (HBP) to discuss drugs and nursing management. In the past, use of the term hypertension created the impression that a person would be feeling “hyper” if his or her blood pressure was too high, when in fact HBP is often without symptoms. When patients felt calm, they believed their blood pressure was normal; therefore they did not think they needed drugs. This led to much confusion between patients and their healthcare providers. HBP is a much simpler term, and patients understand it better than hypertension. According to the American Heart Association, HBP affects as many as one in three adults 20 years of age or older. Although the exact cause of HBP is unknown, there are a number of risk factors, including a family history of HBP, African American race, overweight or obesity, physical inactivity, current cigarette smoking or exposure to secondhand smoke, and too much alcohol consumption. People with diabetes, elevated blood lipids, or kidney disease also are at higher risk for HBP. Risk increases with age, so it is not surprising that as the population ages, there will be a need for a good understanding of HBP management. Whatever the cause, when HBP is untreated or poorly treated, people can develop serious health problems and even death. Severity of HBP is classified according to the stages listed in Table 8.5. These stages were recently revised to recommend the elimination of the term “prehypertension” for the more accurate term “elevated” blood pressure. Accurate diagnosis is essential to determination of the best treatments for your patients. As an LPN, you will have an important role in using the proper technique for blood 264 pressure screening. In addition, you will work with the health care team to reinforce recommended lifestyle changes (Box 8.2). If lifestyle changes alone are not effective in reducing the patient's blood pressure, healthcare providers begin drug therapy. Choices of prescribed drugs may depend on the patient's age, race, and whether the patient has diabetes or chronic kidney disease (which can complicate treatment). Do not hesitate to communicate with the health care provider if you are not clear about your patient's blood pressure goals. Table 8.5 Blood Pressure Classification CLASSIFICATION BLOOD PRESSURE MEASUREMENT Normal Systolic and diastolic Elevated Systolic or diastolic Stage 1 hypertension Systolic or diastolic Stage 2 hypertension Systolic and diastolic BLOOD PRESSURE READING <120 mm Hg <80 mm Hg 120–129 mm Hg <80 mm Hg 130–139 mm Hg 80–89 mm Hg ≥140 mm Hg ≥90 mm Hg From Whelton PK, Carey RM, Aronow WS, et al. (2017). ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA Guideline for the prevention, detection, evaluation, and management of high blood pressure in adults: A report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines. J Am Coll Cardiol Nov 13: [Epub ahead of print]. Box 8.2 Recommended Lifestyle Changes for Patients With High Blood Pressure Stop smoking. Eat a well-balanced diet. Decrease sodium (salt) intake. Explore ways to reduce stressors in your life. Maintain a healthy weight. Try to get 40 minutes of moderate-intensity exercise three to four times each week. Limit alcohol to no more than two drinks a day for men or one drink per day for women. Avoid all over-the-counter drugs that can raise blood pressure. Antihypertensives are drugs that have the main purpose of lowering blood pressure. A variety of drugs can lower blood pressure by different mechanisms. Not all patients respond to any one class of blood pressure–lowering drugs in the same way. Drug therapy for HBP often requires trial periods to establish the right drug or drug combinations to help any one patient achieve his or her blood pressure goal. For the general population, non-African American patients typically begin with thiazide diuretics. These drugs may be prescribed alone or in combination with 265 angiotensin-converting enzyme inhibitors (ACE-Is) or angiotensin II receptor blockers (ARBs). For African American patients, thiazide diuretics and calcium channel blockers are used alone or in combination for best management. For patients with diabetes and/or chronic kidney disease, ACE-Is and ARBs are used. Additional classes of drugs used in management of HBP most commonly include beta blockers, alpha blockers, alpha2 agonists, combined alpha and beta blockers, and vasodilators. Although the actions for the antihypertensives drugs differ, some nursing implications are the same for all of them. Box 8.3 describes these common nursing considerations for giving antihypertensive drugs. Nursing considerations and patient teaching issues specific to any single drug type are listed with the individual antihypertensive drug categories. Box 8.3 General Nursing Implications for Antihypertensive Drug Therapy Assessment • Gather baseline vital signs before giving any drug for HBP. • Get a complete list of all drugs that the patient is currently taking, including prescription, over-the-counter, and herbal drugs. • Assess patient's use of alcohol and/or illegal drugs that might interfere with the drug therapy or increase risk for adverse effects. • Review patient's laboratory work, particularly relating to kidney tests (blood urea nitrogen and creatinine levels), as well as serum sodium and potassium concentrations. • Assess for fluid balance including the presence of edema or symptoms of dehydration. Planning and Implementation • Teach patient to report all over-the-counter drugs, checking with the healthcare provider to avoid dangerous drug interactions. • Remind patient to avoid sudden chang