| AMIODARONE HYDROCHLORIDe
Cordarone, Amio-Aqueous, Pacerone
Classifications: antiarrhythmic, class iii; Therapeutic: antiarrhythmic, class iii; antianginal
Pregnancy Category: D
200 mg tablets; 50 mg/mL injection
Class III antiarrhythmic; also has antianginal and antiadrenergic properties. Acts directly on all cardiac tissues by prolonging
duration of action potential and refractory period without significantly affecting resting membrane potential.
By direct action on smooth muscle, decreases peripheral resistance and increases coronary blood flow. Blocks effects of
Prophylaxis and treatment of life-threatening ventricular arrhythmias and supraventricular arrhythmias, particularly with
Treatment of nonexertional angina, conversion of atrial fibrillation to normal sinus rhythm, paroxysmal supraventricular
tachycardia, ventricular rate control due to accessory pathway conduction in pre-excited atrial arrhythmia, after defibrillation
and epinephrine in cardiac arrest, AV nodal reentry tachycardia.
Hypersensitivity to amiodarone, or benzyl alcohol; cardiogenic shock, severe sinus bradycardia, advanced AV block unless
a pacemaker is available, severe sinus-node dysfunction or sick sinus syndrome, bradycardia, congenital or acquired QR prolongation
syndromes, or history of torsade de pointes; severe liver disease, pregnancy (category D), lactation.
Hepatic disease, cirrhosis; Hashimoto's thyroiditis, goiter, thyrotoxicosis, or history of other thyroid dysfunction; CHF,
left ventricular dysfunction; hypersensitivity to iodine; older adults; Fabry disease, especially with visual disturbances;
electrolyte imbalance, hypokalemia, hypomagnesemia, hypovolemia; preexisting lung disease, COPD; open heart surgery.
Route & Dosage
Adult: PO Loading Dose 8001600 mg/d in 12 doses for 13 wk PO Maintenance Dose 400600 mg/d in 12 doses IV Loading Dose 150 mg over 10 min followed by 360 mg over next 6 h IV Maintenance Dose 540 mg over 18 h (0.5 mg/min), may continue at 0.5 mg/min Convert IV to PO Duration of infusion <1 wk use 8001600 mg PO, 13 wk use 600800 mg PO, >3 wk use 400 mg PO
Child: IV 5 mg/kg then repeat to max of 300 mg total
Adjustment only suggested in severe hepatic impairment.
- Note: Correct hypokalemia and hypomagnesemia prior to initiation of therapy.
- Give consistently with respect to meals.
- Note: Only a physician experienced with the drug and treatment of life-threatening arrhythmias should give loading doses.
- Note: GI symptoms commonly occur during high-dose therapy, especially with loading doses. Symptoms usually respond to dose reduction
or divided dose given with food, including milk.
PREPARE: IV Infusion: First rapid loading dose infusion: Add 150 mg (3 mL) amiodarone to 100 mL D5W to yield 1.5 mg/mL. Second infusion during first 24 h (slow loading dose and maintenance infusion): Add 900 mg (18 mL) amiodarone to 500 mL D5W to yield 1.8 mg/mL. Maintenance infusions after the first 24 h: Prepare concentrations of 16 mg/mL amiodarone. Note: Use central line to give concentrations >2 mg/mL.
ADMINISTER: IV Infusion: Rapidly infuse initial 150 mg dose over the first 10 min at a rate of 15 mg/min. Over next 6 h, infuse 360 mg at a rate
of 1 mg/min. Over the remaining 18 h, infuse 540 mg at a rate of 0.5 mg/min. After the first 24 h, infuse maintenance doses
of 720 mg/24 h at a rate of 0.5 mg/min.
INCOMPATIBILITIES Solution/additive: Aminophylline, cefazolin, furosemide, quinidine. Y-site: Aminophylline, ampicillin/sulbactam, argatroban, bivalirudin, cefamandole, cefazolin, ceftazidime, digoxin, drotrecogin, heparin, imipenem/cilastatin, magnesium sulfate, piperacillin, piperacillin/tazobactam, potassium phosphate, sodium bicarbonate, sodium nitroprusside, sodium phosphate.
- Store at 15°30° C (59°86° F) protected from light, unless otherwise directed.
Adverse Effects (≥1%)CNS:
wasting numbness, tingling), fatigue,
abnormal gait, dyskinesias, dizziness, paresthesia
, headache. CV:
), sinus arrest, cardiogenic shock,
CHF, arrhythmias; AV block. Special Senses: Corneal microdeposits,
blurred vision, optic neuritis
, optic neuropathy
, permanent blindness, corneal degeneration, macular degeneration, photosensitivity. GI: Anorexia, nausea, vomiting, constipation, hepatotoxicity. Metabolic:
Hyperthyroidism or hypothyroidism; may cause neonatal
hypo- or hyperthyroidism if taken during pregnancy. Respiratory:
) Alveolitis, pneumonitis (fever, dry cough, dyspnea
), interstitial pulmonary
fibrosis, fatal gasping syndrome
in children. Skin:
Slate-blue pigmentation, photosensitivity,
With chronic use, angioedema.
Significantly increases digoxin
levels; enhances pharmacologic effects and toxicities of disopyramide, procainamide, quinidine, flecainide, lidocaine, lovastatin, simvastatin;
anticoagulant effects of oral anticoagulants
enhanced; verapamil, diltiazem, beta-adrenergic blocking agents
may potentiate sinus bradycardia, sinus arrest, or AV block; may increase phenytoin
levels 2- to 3-fold; cholestyramine
may decrease amiodarone levels; fentanyl
may cause bradycardia, hypotension, or decreased output; may increase cyclosporine
levels and toxicity
may increase amiodarone levels; ritonavir
may increase risk of amiodarone toxicity
, including cardiotoxicity. Herbal: Echinacea
possible increase in hepatotoxicity.
2286% absorbed. Onset:
23 d to 13 wk. Peak:
37 h. Distribution:
Concentrates in adipose tissue
, lungs, kidneys, spleen; crosses placenta. Metabolism:
Extensively in liver; undergoes some enterohepatic cycling; via CYP2C8 and 3A4. Elimination:
Excreted chiefly in bile and feces; also in breast milk. Half-Life:
Biphasic, initial 2.510 d, terminal 4055 d.
Assessment & Drug Effects
- Monitor BP carefully during infusion and slow the infusion if significant hypotension occurs; bradycardia should be treated
by slowing the infusion or discontinuing if necessary. Monitor heart rate and rhythm and BP until drug response has stabilized;
report promptly symptomatic bradycardia. Sustained monitoring is essential because drug has an unusually long half-life.
- Monitor for S&S of: Adverse effects, particularly conduction disturbances and exacerbation of arrhythmias, in patients receiving
concomitant antiarrhythmic therapy (reduce dosage of previous agent by 3050% several days after amiodarone therapy
is started); drug-induced hypothyroidism or hyperthyroidism (see Appendix F), especially during early treatment period; pulmonary
toxicity (progressive dyspnea, fatigue, cough, pleuritic pain, fever) throughout therapy.
- Lab tests: Baseline and periodic assessments should be made of liver, lung, thyroid, neurologic, and GI function. Drug may
cause thyroid function test abnormalities in the absence of thyroid function impairment.
- Monitor for elevations of AST and ALT. If elevations persist or if they are 23 times above normal baseline readings,
reduce dosage or withdraw drug promptly to prevent hepatotoxicity and liver damage.
- Auscultate chest periodically or when patient complains of respiratory symptoms. Check for diminished breath sounds, rales,
pleuritic friction rub; observe breathing pattern. Drug-induced pulmonary function problems must be distinguished from CHF
or pneumonia. Keep physician informed.
- Anticipate possible CNS symptoms within a week after amiodarone therapy begins. Proximal muscle weakness, a common side effect,
intensified by tremors presents a great hazard to the ambulating patient. Assess severity of symptoms. Supervision of ambulation
may be indicated.
Patient & Family Education
- Check pulse daily once stabilized, or as prescribed. Report a pulse <60.
- Take oral drug consistently with respect to meals.
- Become familiar with potential adverse reactions and report those that are bothersome to the physician.
- Use dark glasses to ease photophobia; some patients may not be able to go outdoors in the daytime even with such protection.
- Follow recommendation for regular ophthalmic exams, including funduscopy and slit-lamp exam.
- Wear protective clothing and a barrier-type sunscreen that physically blocks penetration of skin by ultraviolet light (e.g.,
titanium oxide or zinc formulations) to prevent a photosensitivity reaction (erythema, pruritus); avoid exposure to sun and