Mosby's 2014 Nursing Drug Reference (11 page)
Read Mosby's 2014 Nursing Drug Reference Online
Authors: Linda Skidmore-Roth
Calcium channel blockers act by inhibiting calcium ion influx across the cell membrane in cardiac and vascular smooth muscle. This action produces relaxation of coronary vascular smooth muscle, dilates coronary arteries, slows SA/AV node conduction, and dilates peripheral arteries.
Calcium channel blockers are used for chronic stable angina pectoris, vasospastic angina, dysrhythmias, hypertension, and unstable angina.
Persons with 2nd-/3rd-degree heart block, sick sinus syndrome, hypotension of <90 mm Hg systolic, Wolff-Parkinson-White syndrome, or cardiogenic shock should not use these products; worsening of those conditions may occur.
Precautions:
Congestive heart failure because edema may be increased. Hypotension may worsen because B/P is decreased. Patients with renal/hepatic disease should use these products cautiously because they are metabolized in the liver and excreted by the kidneys.
•
PO before meals and at bedtime
The most common side effects are dysrhythmias and edema. Also common are headache, fatigue, drowsiness, and flushing.
Onset, peak, and duration vary widely with route of administration. Products are metabolized by the liver and excreted in the urine primarily as metabolites.
Increased levels of digoxin and theophylline may occur when used with these products. Increased effects of β-blockers and antihypertensives may occur with calcium channel blockers.
•
Decreased cardiac output
[adverse reactions]
•
Ineffective cardiac tissue perfusion
[uses]
•
Cardiac system: B/P, pulse, respirations, ECG intervals (PR, QRS, QT)
•
Therapeutic response: decreased anginal pain; decreased B/P, dysrhythmias
•
How to take pulse before taking product; patient should record or graph pulses to identify changes
•
To avoid hazardous activities until stabilized on this product because dizziness commonly occurs
•
The need for compliance in all areas of medical regimen, including diet, exercise, stress reduction, and product therapy
isradipine
Cardiac glycosides act by inhibiting sodium and potassium ATPase and then making more calcium available to activate contracted proteins. Cardiac contractility and cardiac output are increased.
Cardiac glycosides are used for congestive heart failure, atrial fibrillation, atrial flutter, atrial tachycardia, and rapid digitalization in these disorders.
Hypersensitive reactions may occur, and allergies should be identified before these products are given. Also, persons with ventricular tachycardia, ventricular fibrillation, and carotid sinus syndrome should not use these products.
Precautions:
Persons with acute MI and those who have or may develop serum potassium, calcium, or magnesium imbalances should use these products cautiously. Also, geriatric patients and those with AV block, severe respiratory disease, hypothyroidism, or renal/hepatic disease should exercise caution when these products are prescribed.
•
Potassium supplements if ordered for potassium levels <3 mg/dl
The most common side effects are cardiac disturbances, headache, hypotension, and GI symptoms. Also common are blurred vision and yellow-green halos.
Onset, peak, and duration vary widely with the route of administration. Digitoxin is inactivated by the liver, and inactive metabolites are excreted in urine. Digoxin is excreted in urine mainly as the parent product and metabolites.
Toxicity may occur when used with diuretics, succinylcholine, quiNIDine, and thioamines. Increased blood levels may occur with propantheline bromide, spironolactone, quiNIDine, verapamil, aminoglycosides (PO), amiodarone, anticholinergics, and quiNINE. Diuretics may increase toxicity.
•
Decreased cardiac output
[adverse reactions]
•
Ineffective cardiac tissue perfusion
[uses]
•
Cardiac system: B/P, pulse, respirations, and increased urine output
•
Apical pulse for 1 min before giving product; if pulse <60 bpm, take again in 1 hr; if still <60 bpm, notify prescriber
•
Electrolytes: K, Na, Cl, Mg; renal function studies, including BUN and creatinine; and blood studies, including AST, ALT, bilirubin
•
I&O ratio, daily weights
•
Monitor therapeutic product levels
•
Therapeutic response: decreased weight, edema, pulse, respiration; increased urine output
•
How to take pulse before taking prod
uct; patient should record or graph pulse to identify changes
•
To avoid hazardous activities until stabilized on this product; dizziness commonly occurs
•
About the need for compliance in all areas of medical regimen, including diet, exercise, stress reduction, product therapy
Cholinergics act by preventing destruction of acetylcholine, which increases concentration at sites where acetylcholine is released. This exaggerates the effects of acetylcholine and facilitates transmission of impulses across the myoneural junction. Cholinergics may also act by stimulating receptors for acetylcholine.
Cholinergics are used for myasthenia gravis, as antagonists of nondepolarizing neuromuscular blockade, postoperative bladder distention and urinary distention, and postoperative ileus.
Persons with obstruction of the intestine or renal system should not use these products.
Precautions:
Caution should be used in patients with bradycardia, hypotension, seizure disorders, bronchial asthma, coronary occlusion, hyperthyroidism, breastfeeding, and in children.
•
Only with atropine sulfate available for cholinergic crisis
•
Only after all other cholinergics have been discontinued
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Increased doses if tolerance occurs
•
Larger doses after exercise or fatigue
•
On empty stomach for better absorption
The most serious adverse reactions are respiratory depression, bronchospasm, constriction, laryngospasm, respiratory arrest, seizures, and paralysis. The most common side effects are nausea, diarrhea, and vomiting.
Onset, peak, and duration vary widely among products. Most products are metabolized in the liver and excreted in urine.
Interactions vary widely among products. Check individual monographs for specific information.
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Deficient knowledge
[teaching]
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Noncompliance
[teaching]
•
Impaired urinary elimination
[uses]
•
VS, respiration q8hr
•
I&O ratio; check for urinary retention or incontinence
•
Bradycardia, hypotension, bronchospasm, headache, dizziness, seizures, respiratory depression; product should be discontinued if toxicity occurs
•
Storage at room temperature
•
Therapeutic response: increased muscle strength, hand grasp; improved muscle gait; absence of labored breathing (if severe)
•
That product is not a cure; it only relieves symptoms (myasthenia gravis)
•
To carry emergency ID specifying myasthenia gravis, products taken
Cholinergic blockers inhibit or block acetylcholine at receptor sites in the autonomic nervous system.
Many cholinergic blockers are used to decrease secretions before surgery, to reverse neuromuscular blockade, and to decrease motility of GI, biliary, urinary tracts. Other products are used for parkinsonian symptoms, including dystonia associated with neuroleptic products.
Hypersensitivity can occur, and allergies should be identified before administering these products. Persons with GI and GU obstruction should not use these products since constipation and urinary retention may occur. They are also contraindicated in closed-angle glaucoma and myasthenia gravis.
Precautions:
Caution must be used when these products are given to geriatric patients since metabolism is slowed. Also, persons with tachycardia or prostatic hypertrophy should use these products with caution.
•
With food or milk to decrease GI symptoms
•
Parenteral dose with patient recumbent to prevent postural hypotension; give parenteral dose slowly, monitoring vital signs
The most common side effects are dryness of the mouth and constipation, which can be prevented by frequent rinsing of the mouth and by increasing water and bulk in the diet.
Onset, peak, and duration vary with route.
Increase in anticholinergic effect occurs when used with opioids, barbiturates, antihistamines, MAOIs, phenothiazines, and amantadine.
•
Impaired physical mobility
[uses]
•
Chronic pain
[uses]
•
I&O ratio; be alert for urinary retention, frequency, dysuria; product should be discontinued if these occur
•
Urinary hesitancy, retention; palpate bladder if retention occurs
•
Constipation; increase fluids, bulk, exercise
•
For tolerance over long-term therapy; dose may have to be increased or changed
•
Mental status: affect, mood, CNS depression, worsening of mental symptoms during early therapy
•
Hard candy, gum, frequent rinsing of mouth for dryness
•
Therapeutic response: absence of cramps and EPS
•
To avoid driving, other hazardous activities if drowsiness occurs
•
To avoid concurrent use of cough, cold preparations with alcohol, antihistamines unless directed by prescriber
•
To use with caution in hot weather because medication may increase susceptibility to heat stroke
Corticosteroids are divided into glucocorticoids and mineralocorticoids. Glucocorticoids decrease inflammation by the suppression of migration of polymorphonuclear leukocytes, fibroblasts, increased capillary permeability, and lysosomal stabilization. They also have varied metabolic effects and modify the body’s immune responses to many stimuli. Mineralocorticoids act by increasing resorption of sodium by increasing hydrogen and potassium excretion in the distal tubule.
Glucocorticoids are used to decrease inflammation and for immunosuppression. In addition, some products may be given for allergy, adrenal insufficiency, or cerebral edema. Mineralocorticoids are given for adrenal insufficiency or adrenogenital syndrome.
Hypersensitivity may occur and should be identified before administering. Because these products mask infection, they should not be used in systemic fungal infections or amebiasis. Mothers taking pharmacologic doses of corticosteroids should not breastfeed.
Precautions:
Caution must be used when these products are prescribed for diabetic patients because hyperglycemia may occur. Also, patients with glaucoma, seizure disorders, peptic ulcer, impaired renal function, congestive heart failure, hypertension, ulcerative colitis, or myasthenia gravis should be monitored closely if corticosteroids are given. Use with caution in children, the geriatric patients, and during pregnancy.
•
With food or milk to decrease GI symptoms
•
Take single daily or alternate-day doses in the morning before 9
AM
(for replacement therapy)
The most common side effects include change in behavior, including insomnia and euphoria; GI irritation, including peptic ulcer; metabolic reactions, including hypokalemia, hyperglycemia, and carbohydrate intolerance; and sodium and fluid retention. Most adverse reactions are dose-dependent.
For oral preparations, the onset of action occurs between 1 and 2 hr, and duration can be up to 2 days, with a half-life of 2-4 days. Pharmacokinetics vary widely among products. These products cross the placenta and appear in breast milk.
Decreased corticosteroid effect may occur with barbiturates, rifampin, and phenytoin; corticosteroid dose may have to be increased. There is a possibility of GI bleeding when used with salicylates and indomethacin. Corticosteroids may reduce salicylate levels. When using with digoxin, glycosides, potassium-depleting diuretics, and amphotericin, serum potassium levels should be monitored.
•
Disturbed body image
[adverse reactions]
•
Risk for infection
[adverse reactions]
•
Risk for suicide
[adverse reactions]
•
Potassium, blood glucose, urine glucose while on long-term therapy; hypokalemia and hyperglycemia are common
•
Weight daily; notify prescriber of weekly gain >5 lb because these products alter fluid and electrolyte balance
•
I&O ratio; be alert for decreasing urinary output and increasing edema
•
Plasma cortisol levels during long-term therapy (normal level is 138-635 nmol/L SI units when drawn at 8
AM
)
•
Infection: increased temp, WBC, even after withdrawal of medication; product masks symptoms of infection
•
Adrenal insufficiency: nausea, anorexia, fatigue, dizziness, dyspnea, weakness, joint pain
•
Potassium depletion: paresthesias, fatigue, nausea, vomiting, depression, polyuria, dysrhythmias, weakness
•
Mental status: affect, mood, behavioral changes, aggression; if severe personality changes occur, including depression, product may have to be tapered and then discontinued
•
Therapeutic response: decreased inflammation
•
That emergency ID as steroid user should be carried
•
Not to discontinue this medication abruptly; adrenal crisis can result
•
All aspects of product use, including cushingoid symptoms
•
To take with meals or a snack
•
To avoid exposure to chickenpox or measles if taking immunosuppressives
