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High Alert
amiodarone (am-ee-oh-da-rone)
Cordarone, Nexterone, Pacerone
Classification
Therapeutic: antiarrhythmics (class III)
Pregnancy Category D
Indications
Life-threatening ventricular arrhythmias unresponsive to less toxic agents. Unlabeled Use: PO: Management of supraventricular tachyarrhythmias. IV: As part of
the Advanced Cardiac Life Support (ACLS) and Pediatric Advanced Life Support
(PALS) guidelines for the management of ventricular fibrillation (VF)/pulseless ventricular tachycardia (VT) after cardiopulmonary resuscitation and defibrillation have
failed; also for other life-threatening tachyarrhythmias.
Action
Prolongs action potential and refractory period. Inhibits adrenergic stimulation.
Slows the sinus rate, increases PR and QT intervals, and decreases peripheral vascular resistance (vasodilation). Therapeutic Effects: Suppression of arrhythmias.
Pharmacokinetics
Absorption: Slowly and variably absorbed from the GI tract (35– 65%). IV administration results in complete bioavailability.
Distribution: Distributed to and accumulates slowly in body tissues. Reaches high
levels in fat, muscle, liver, lungs, and spleen. Crosses the placenta and enters breast
milk.
Protein Binding: 96% bound to plasma proteins.
Metabolism and Excretion: Metabolized by the liver, excreted into bile. Minimal renal excretion. One metabolite has antiarrhythmic activity.
Half-life: 13– 107 days.
TIME/ACTION PROFILE (suppression of ventricular arrhythmias)
ROUTE
ONSET
PEAK
DURATION
PO
2–3 days (up to 2–3
mo)
2 hr
3–7 hr
wk–mos
3–7 hr
unknown
IV
⫽ Canadian drug name.
⫽ Genetic Implication.
Plate # 0-Composite
pg 1 # 1
Contraindications/Precautions
Contraindicated in: Patients with cardiogenic shock; Severe sinus node dysfunction; 2nd- and 3rd-degree AV block; Bradycardia (has caused syncope unless a pacemaker is in place); Hypersensitivity to amiodarone or iodine; OB: Can cause fetal
hypo- or hyperthyroidism; Lactation: Enters breast milk and can cause harm to the
neonate; use an alternative to breast milk; Pedi: Safety not established; products containing benzyl alcohol should not be used in neonates.
Use Cautiously in: History of HF; Thyroid disorders; Corneal refractive laser surgery; Severe pulmonary or liver disease; Geri: Initiate therapy at the low end of the
dosing range due tophepatic, renal, or cardiac function; comorbid disease; or other
drug therapy.
Adverse Reactions/Side Effects
CNS: confusional states, disorientation, hallucinations, dizziness, fatigue, malaise,
headache, insomnia. EENT: corneal microdeposits, abnormal sense of smell, dry
eyes, optic neuritis, optic neuropathy, photophobia. Resp: ADULT RESPIRATORY DISTRESS SYNDROME (ARDS), PULMONARY FIBROSIS, PULMONARY TOXICITY. CV: CHF, WORSENING OF ARRHYTHMIAS, bradycardia, hypotension. GI: anorexia, constipation, nausea, vomiting, abdominal pain, abnormal sense of taste,qliver enzymes. GU: p
libido, epididymitis. Derm: TOXIC EPIDERMAL NECROLYSIS (rare), photosensitivity,
blue discoloration. Endo: hypothyroidism, hyperthyroidism. Neuro: ataxia, involuntary movement, paresthesia, peripheral neuropathy, poor coordination, tremor.
Interactions
Drug-Drug:qrisk of QT prolongation with fluoroquinolones, macrolides, and
azole antifungals (undertake concurrent use with caution).qlevels of digoxin
(pdose of digoxin by 50%).qlevels of class I antiarrhythmics (quinidine, mexiletine, lidocaine, or flecainide—pdoses of other drugs by 30– 50%).qlevels of
cyclosporine, dextromethorphan, methotrexate, phenytoin, carvedilol, and
theophylline. Phenytoinpamiodarone levels.qactivity of warfarin (pdose of
warfarin by 33– 50%).qrisk of bradyarrhythmias, sinus arrest, or AV heart block
with beta blockers or calcium channel blockers. Cholestyramine maypamiodarone levels. Cimetidine and ritonavirqamiodarone levels. Risk of myocardial
depression isqby volatile anesthetics.qrisk of myopathy with lovastatin and
simvastatin (do not exceed 40 mg/day of lovastatin or 20 mg/day of simvastatin).
Drug-Natural Products: St. John’s wort induces enzymes that metabolize amiodarone; mayplevels and effectiveness. Avoid concurrent use.
CAPITALS indicate life-threatening, underlines indicate most frequent.
Strikethrough ⫽ Discontinued.
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Drug-Food: Grapefruit juice inhibits enzymes in the GI tract that metabolize amiodarone resulting inqlevels and risk of toxicity; avoid concurrent use.
Route/Dosage
Ventricular Arrhythmias
PO (Adults): 800– 1600 mg/day in 1– 2 doses for 1– 3 wk, then 600– 800 mg/day
in 1– 2 doses for 1 mo, then 400 mg/day maintenance dose.
PO (Children): 10 mg/kg/day (800 mg/1.72 m2/day) for 10 days or until response
or adverse reaction occurs, then 5 mg/kg/day (400 mg/1.72 m2/day) for several
weeks, thenpto 2.5 mg/kg/day (200 mg/1.72 m2/day) or lowest effective maintenance dose.
IV (Adults): 150 mg over 10 min, followed by 360 mg over the next 6 hr and then
540 mg over the next 18 hr. Continue infusion at 0.5 mg/min until oral therapy is initiated. If arrhythmia recurs, a small loading infusion of 150 mg over 10 min should be
given; in addition, the rate of the maintenance infusion may beq. Conversion to initial oral therapy— If duration of IV infusion was ⬍1 wk, oral dose should be 800–
1600 mg/day; if IV infusion was 1– 3 wk, oral dose should be 600– 800 mg/day; if IV
infusion was ⬎3 wk, oral dose should be 400 mg/day. ACLS guidelines for pulseless
VF/VT— 300 mg IV push, may repeat once after 3– 5 min with 150 mg IV push (maximum cumulative dose 2.2 g/24 hr; unlabeled).
IVIntraosseous (Children and infants): PALS guidelines for pulseless VF/VT—
5 mg/kg as a bolus; Perfusion tachycardia— 5 mg/kg loading dose over 20– 60
min (maximum of 15 mg/kg/day; unlabeled).
Supraventricular Tachycardia
PO (Adults): 600– 800 mg/day for 1 wk or until desired response occurs or side
effects develop, thenpto 400 mg/day for 3 wk, then maintenance dose of 200– 400
mg/day.
PO (Children): 10 mg/kg/day (800 mg/1.72 m2/day) for 10 days or until response
or side effects occur, then 5 mg/kg/day (400 mg/1.72 m2/day) for several weeks,
thenpto 2.5 mg/kg/day (200 mg/1.72 m2/day) or lowest effective maintenance dose.
NURSING IMPLICATIONS
Assessment
● Monitor ECG continuously during IV therapy or initiation of oral ther-
apy. Monitor heart rate and rhythm throughout therapy; PR prolonga-
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pg 2 # 2
tion, slight QRS widening, T-wave amplitude reduction with T-wave widening and bifurcation, and U waves may occur. QT prolongation may be
associated with worsening of arrhythmias and should be monitored
closely during IV therapy. Report bradycardia or increase in arrhythmias promptly; patients receiving IV therapy may require slowing rate,
discontinuing infusion, or inserting a temporary pacemaker.
Assess pacing and defibrillation threshold in patients with pacemakers and implanted defibrillators at beginning and periodically during therapy.
Assess for signs of pulmonary toxicity (rales/crackles, decreased breath
sounds, pleuritic friction rub, fatigue, dyspnea, cough, wheezing, pleuritic pain, fever, hemoptysis, hypoxia). Chest x-ray and pulmonary function tests are recommended before therapy. Monitor chest x-ray every
3– 6 mo during therapy to detect diffuse interstitial changes or alveolar
infiltrates. Bronchoscopy or gallium radionuclide scan may also be used
for diagnosis. Usually reversible after withdrawal, but fatalities have occurred.
IV: Assess for signs and symptoms of ARDS throughout therapy. Report
dyspnea, tachypnea, or rales/crackles promptly. Bilateral, diffuse pulmonary infiltrates are seen on chest x-ray.
Monitor BP frequently. Hypotension usually occurs during first several hours of
therapy and is related to rate of infusion. If hypotension occurs, slow rate.
PO: Assess for neurotoxicity (ataxia, proximal muscle weakness, tingling or
numbness in fingers or toes, uncontrolled movements, tremors); common during
initial therapy, but may occur within 1 wk to several mo of initiation of therapy and
may persist for more than 1 yr after withdrawal. Dose reduction is recommended.
Assist patient during ambulation to prevent falls.
Ophthalmic exams should be performed before and regularly during therapy and
whenever visual changes (photophobia, halos around lights, decreased acuity)
occur. May cause permanent loss of vision.
Assess for signs of thyroid dysfunction, especially during initial therapy. Lethargy;
weight gain; edema of the hands, feet, and periorbital region; and cool, pale skin
suggest hypothyroidism and may require decrease in dose or discontinuation of
therapy and thyroid supplementation. Tachycardia; weight loss; nervousness; sensitivity to heat; insomnia; and warm, flushed, moist skin suggest hyperthyroidism
and may require discontinuation of therapy and treatment with antithyroid agents.
Lab Test Considerations: Monitor liver and thyroid functions before
and every 6 mo during therapy. Drug effects persist long after discontinuation.
䉷 2015 F.A. Davis Company
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amiodarone
●
Thyroid function abnormalities are common, but clinical thyroid dysfunction is
uncommon.
● Monitor AST, ALT, and alkaline phosphatase at regular intervals during therapy,
especially in patients receiving high maintenance dose. If liver function studies are
3 times normal or double in patients with elevated baseline levels or if hepatomegaly occurs, dose should be reduced.
● May cause asymptomaticqin ANA titer concentrations.
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Potential Nursing Diagnoses
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Decreased cardiac output (Indications)
Impaired gas exchange (Side Effects)
Implementation
● High Alert: IV vasoactive medications are inherently dangerous; fatalities have
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pg 3 # 3
● Infusions exceeding 2 hr must be administered in glass or polyolefin bottles to
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Plate # 0-Composite
occurred from medication errors involving amiodarone. Before administering,
have second practitioner check original order, dose calculations, and infusion
pump settings. Patients should be hospitalized and monitored closely during IV
therapy and initiation of oral therapy. IV therapy should be administered only by
physicians experienced in treating life-threatening arrhythmias.
Do not confuse amiodarone with amantadine.
Hypokalemia and hypomagnesemia may decrease effectiveness or cause additional arrhythmias; correct before therapy.
Monitor closely when converting from IV to oral therapy, especially in geriatric patients.
PO: May be administered with meals and in divided doses if GI intolerance occurs
or if daily dose exceeds 1000 mg.
IV Administration
● pH: 4.1.
● IV: Administer via volumetric pump; drop size may be reduced, causing altered
dosing with drop counter infusion sets.
● Administer through an in-line filter.
⫽ Canadian drug name.
⫽ Genetic Implication.
●
prevent adsorption. However, polyvinyl chloride (PVC) tubing must be used during administration because concentrations and infusion rate recommendations
have been based on PVC tubing.
Direct IV: Diluent: Administer undiluted. May also be diluted in 20– 30 mL of
D5W or 0.9% NaCl. Concentration: 50 mg/mL. Rate: Administer IV push.
Intermittent Infusion: Diluent: Dilute 150 mg of amiodarone in 100 mL of
D5W. Infusion stable for 2 hr in PVC bag, or use pre-mixed bags. Concentration: 1.5 mg/mL. Rate: Infuse over 10 min. Do not administer IV push.
Continuous Infusion: Diluent: Dilute 900 mg (18 mL) of amiodarone in 500
mL of D5W. Infusion stable for 24 hr in glass or polyolefin bottle. Concentration: 1.8 mg/mL. Concentration may range from 1– 6 mg/mL (concentrations ⬎2
mg/mL must be administered via central venous catheter). Rate: Infuse at a rate
of 1 mg/min for the first 6 hr, then decrease infusion rate to 0.5 mg/min and continue until oral therapy initiated.
Y-Site Compatibility: alemtuzumab, amikacin, amphotericin B colloidal, amphotericin B lipid complex, anidulafungin, atracurium, atropine, bleomycin,
bumetanide, calcium chloride, calcium gluconate, carboplatin, caspofungin, ceftaroline, ceftriaxone, cefuroxime, ciprofloxacin, cisatracurium, cisplatin, clindamycin, cyclophosphamide, dactinomycin, daptomycin, dexmedetomidine, diltiazem, dobutamine, docetaxel, doripenem, dopamine, doripenem, doxacurium,
doxycycline, epinephrine, erythromycin lactobionate, esmolol, etoposide, etoposide phosphate, famotidine, fenoldopam, fentanyl, fluconazole, gemcitabine, gentamicin, granisetron, haloperidol, idarubicin, ifosfamide, irinotecan, isoproterenol, ketamine, labetalol, lidocaine, linezolid, lorazepam, meperidine,
metaraminol, methylprednisolone, metoprolol, metronidazole, midazolam, milrinone, mitoxantrone, morphine, mycophenolate, nesiritide, nitroglycerin, norepinephrine, octreotide, oxaliplatin, palonosetron, pemetrexed, penicillin G potassium, phentolamine, phenylephrine, potassium chloride, procainamide,
quinupristin/dalfopristin, rifampin, rocuronium, tacrolimus, teniposide, tirofiban, tobramycin, vancomycin, vasopressin, vecuronium, vincristine, vinorelbine,
voriconazole, zoledronic acid.
Y-Site Incompatibility: aminocaproic acid, aminophylline, ampicillin/sulbactam, bivalirudin, ceftazidime, cytarabine, digoxin, doxorubicin hydrochloride, ertapenem, fludarabine, fluorouracil, heparin, imipenem-cilastatin, levofloxacin,
mechlorethamine, methotrexate, micafungin, paclitaxel, piperacillin/tazobactam,
potassium acetate, potassium phosphates, sodium acetate, sodium bicarbonate,
sodium phosphates, yhiopental, thiotepa, tigecycline.
CAPITALS indicate life-threatening, underlines indicate most frequent.
Strikethrough ⫽ Discontinued.
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Patient/Family Teaching
● Instruct patient to take amiodarone as directed. Advise patient to read the Medica●
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tion Guide prior to first dose and with each Rx refill. If a dose is missed, do not
take at all. Consult health care professional if more than two doses are missed.
Advise patient to avoid drinking grapefruit juice during therapy.
Inform patient that side effects may not appear until several days, weeks, or yr after
initiation of therapy and may persist for several mo after withdrawal.
Teach patients to monitor pulse daily and report abnormalities.
Advise patients that photosensitivity reactions may occur through window glass,
thin clothing, and sunscreens. Protective clothing and sunblock are recommended during and for 4 mo after therapy. If photosensitivity occurs, dosage reduction may be useful.
Inform patients that bluish discoloration of the face, neck, and arms is a possible
side effect of this drug after prolonged use. This is usually reversible and will fade
over several mo. Notify health care professional if this occurs.
Instruct male patients to notify health care professional if signs of epididymitis
(pain and swelling in scrotum) occur. May require reduction in dose.
Advise patient to notify health care professional of all Rx or OTC medications, vitamins, or herbal products being taken and to consult with health care professional
before taking other medications, especially St. John’s wort.
Instruct patient to notify health care professional of medication regimen before
treatment or surgery.
Advise patient to notify health care professional if signs and symptoms of thyroid
dysfunction occur.
Caution female patients to avoid breast feeding during therapy.
Emphasize the importance of follow-up exams, including chest x-ray and pulmonary function tests every 3– 6 mo and ophthalmic exams after 6 mo of therapy, and
then annually.
Evaluation/Desired Outcomes
● Cessation of life-threatening ventricular arrhythmias. Adverse effects may take up
to 4 mo to resolve.
Why was this drug prescribed for your patient?
䉷 2015 F.A. Davis Company