Amiodar-100mg

Amiodarone A to Z Drug Facts Amiodarone Action Indications Contraindications Route/Dosage Interactions Lab Test Interferences Adverse Reactions Precautions Patient Care Considerations Administration/Storage Assessment/Interventions Patient/Family Education (A-MEE-oh-duh-rone) Cordarone Tablets: 200 mg, Injection: 50 mg/mL, Pacerone, Tablets: 200 mg, Tablets: 400 mg Class: Antiarrhythmic Action Prolongs action potential duration and refractory period in myocardial cells; acts as noncompetitive inhibitor of alpha- and beta-adrenergic receptors. Indications Oral Treatment of life-threatening, recurrent ventricular arrhythmias (ie, ventricular fibrillation and hemodynamically unstable ventricular tachycardia) that do not respond to other antiarrhythmic agents. Use only in patients with the indicated life-threatening arrhythmias because its use is accompanied by substantial toxicity. Parenteral Initiation of treatment and prophylaxis of frequently recurring ventricular fibrillation and hemodynamically unstable ventricular tachycardia in patients refractory to other therapy; treatment of ventricular tachycardia and fibrillation when oral amiodarone is indicated but patient is unable to take oral medication. Conversion of atrial fibrillation and maintenance of sinus rhythm; treatment of supraventricular tachycardia; IV amiodarone has been used to treat AV nodal reentry tachycardia. Contraindications Oral Severe sinus-node dysfunction, causing marked sinus bradycardia; second- or third-degree atrioventricular (AV) block; when bradycardia produces syncope, unless used with pacemaker; hypersensitivity to the drug. Parenteral Marked sinus bradycardia; second- and third-degree atrioventricular block unless functioning pacemaker is available; cardiogenic shock. Route/Dosage Life-Threatening Recurrent Ventricular Arrhythmias Loading dose: PO 800 to 1600 mg/day for 1 to 3 wk. Reduce doses of other antiarrhythmic agents gradually. When adequate arrhythmia control is achieved, reduce dose to 600 to 800 mg/day for 1 mo. Usual maintenance dose: PO 400 mg/day. Adults: IV Recommended starting dose is » 1000 mg over the first 24 hr administered as follows: rapid administration of 150 mg over first 10 min (15 mg/min), followed by 360 mg over next 6 hr (1 mg/min), then 540 mg over remaining 18 hr (0.5 mg/min). After first 24 hr, continue maintenance infusion rate of 0.5 mg/min (720 mg/24 hr). Paroxysmal Atrial Fibrillation, PSVT, Symptomatic Atrial Flutter PO 600 to 800 mg/day for 7 to 10 days, then 200 to 400 mg/day. Arrhythmias in Patients with CHF PO 200 mg/day. IV to Oral Transition Adults: Clinical monitoring is recommended when changing from IV to oral therapy. PO 800 to 1600 mg amiodarone if duration of IV infusion < 1 wk; 600 to 800 mg amiodarone if duration of IV infusion 1 to 3 wk; 400 mg amiodarone if duration of IV infusion > 3 wk. Interactions Anticoagulants: Effect of anticoagulant may be increased. Use of product may require 30% to 50% decrease in anticoagulant dose. Beta-Blockers: Increased risk of hypotension and bradycardia as well as increased effect of beta blockers eliminated by hepatic metabolism. Calcium Channel Blockers: Increased risk of atrioventricular block with verapamil or diltiazem as well as hypotension with other calcium blockers. Cisapride, Disopyramide, Fluoroquinolones (eg, gatifloxacin, moxifloxacin, sparfloxacin): Possible prolongation of the QT interval, increasing the risk of life-threatening cardiac arrhythmias (including torsades de pointes). Cholestyramine, Rifamycins (eg, rifampin): Amiodarone plasma levels may be reduced, decreasing the pharmacologic effect. Cimetidine, Ritonavir: Amiodarone plasma levels may be elevated, increasing the risk of side effects. Cyclosporine: Elevated plasma concentrations of cyclosporine resulting in elevated creatinine. Dextromethorphan: Increased dextromethorphan plasma levels. Digoxin: Serum digoxin levels may be increased. Fentanyl: Increased risk of hypotension and bradycardia and decreased cardiac output. Flecainide: Serum levels of flecainide may be increased. Hydantoins (eg, phenytoin): Serum concentrations of hydantoins may be increased with potential for symptoms of hydantoin toxicity; also, amiodarone levels may be decreased. Methotrexate, Theophylline: Amiodarone may elevate plasma levels of these agents, increasing the risk of toxicity. Procainamide: Serum levels of procainamide may be increased. Quinidine: Serum quinidine levels may increase, creating potential for fatal cardiac arrhythmias. Lab Test Interferences May alter results of thyroid and LFTs. Adverse Reactions CARDIOVASCULAR: Exacerbation of arrhythmias, CHF, bradycardia, sinoatrial node dysfunction, heart block, sinus arrest, flushing (oral); hypotension, asystole/cardiac arrest, cardiogenic shock, ventricular tachycardia, atrioventricular block (parenteral). CNS: Fatigue; malaise; tremor/abnormal involuntary movements; lack of coordination; abnormal gait/ataxia; dizziness; paresthesias; decreased libido; insomnia; headache; sleep disturbances; abnormal sense of smell. DERMATOLOGIC: Photosensitivity, solar dermatitis, blue discoloration of skin (oral); Stevens-Johnson syndrome (parenteral). EENT: Visual disturbances; visual impairment; blindness; reversible asymptomatic corneal microdeposits; photophobia; abnormal taste. GI: Nausea, vomiting, constipation, anorexia, abdominal pain, abnormal salivation (oral); diarrhea (parenteral). HEMATOLOGIC: Coagulation abnormalities (oral); thrombocytopenia (parenteral). HEPATIC: Nonspecific hepatic disorders. RESPIRATORY: Pulmonary inflammation or fibrosis, progressive dyspnea, pulmonary toxicosis and death (oral); lung edema, respiratory disorder (parenteral). OTHER: Edema, hyperthyroidism or hypothyroidism (oral); fever (parenteral). Precautions Pregnancy: Category D. Lactation: Excreted in breast milk. Children: Safety and efficacy not established. Adult Respiratory Distress Syndrome (ARDS): ARDS has been reported. Benzyl Alcohol: Benzyl alcohol, contained in some of these products as a preservative, has been associated with fatal “gasping syndrome” in children. Ophthalmic Effects: Optic neuropathy or neuritis, resulting in visual impairment may occur. Potential Fatal Toxicities: Pulmonary toxicity and arrhythmias have been reported. PATIENT CARE CONSIDERATIONS Administration/Storage Only use amiodarone in patients with the indicated life-threatening arrhythmias because its use is accompanied by substantial toxicity. Administer with meals. Store at room temperature and protect from light. Assessment Interventions Obtain patient history, including drug history and any known allergies. Review baseline clotting factor studies and serum levels of digoxin, flecainide, quinidine, procainamide, and theophylline, as available, and continue to monitor these parameters during treatment. Review thyroid and LFT results, and note any changes after initiation of therapy. Consult chest x-ray, and review findings from any pulmonary function tests performed prior to and after initiation of therapy. Repeat history and physical examination q 3 to 6 mo, and consult chest radiographs as available. Assess for changes in pulmonary status, and notify health care provider of any trends that could be associated with pulmonary toxicity (eg, dyspnea, fatigue, cough, pleuritic pain). Document and report any fever to health care provider. Assess for symptoms of hyperthyroidism or hypothyroidism. Assess baseline pulse and BP and monitor during treatment. Report symptomatic bradycardia (eg, fatigue, light-headedness, syncope). Assess for CNS side effects (eg, muscle weakness) and report to health care provider. Monitor cardiac rhythm continuously during initiation of treatment and regularly during maintenance therapy. Notify health care provider of exacerbation of presenting arrhythmia, bradycardia, heart block, or sinus arrest. Cases of optic neuropathy or optic neuritis, usually resulting in visual impairment (in some cases permanent blindness), have occurred in patients treated with amiodarone. If symptoms of visual impairment appear, prompt ophthalmic examination is recommended. Appearance of optic neuropathy or neuritis calls for re-evaluation of therapy. Patient/Family Education Instruct patient to report any cough or shortness of breath. Show patient how to take pulse. Explain that heart rates < 60 bpm should be reported to health care provider. Advise patient that regular ophthalmic examination is recommended during administration of amiodarone. Prompt evaluation is required if visual impairment occurs. Caution patient to avoid exposure to sunlight, and to use sunscreen and wear protective clothing to avoid photosensitivity reaction. Sun-exposed skin may appear blue-gray. Also, explain that discomfort of photophobia may be decreased by wearing sunglasses. Explain that eating small, frequent meals or dividing daily dose and taking 2 or 3 doses with meals may help if patient experiences GI upset. Instruct patient to report the following symptoms to health care provider: halos around lights; any vision problems; GI distress; loss of appetite; tremors; twitches; fatigue; unsteady walking; dizziness; numbness and tingling in hands or feet; insomnia; headache; slowing of heartbeat; irregular heart rhythm; difficulty breathing; coughing; sensitivity to sunlight, including blue-gray patches on skin; dermatitis; bruising; hair loss; flushing; abnormal sense of taste or smell; fluid retention; loss of sex drive. Books@Ovid Copyright © 2003 Facts and Comparisons David S. Tatro A to Z Drug Facts -->