about Amiodarone class, uses, side effects contraindications
Amiodarone
Short Description
Amiodarone began to be used in the fifties of the last century, but only in recent years has its use spread as a treatment for a wide range of heart rhythm disorders (Arrhythmia). Amiodarone works by slowing nerve impulses in the heart muscle.
Amiodarone is given to prevent recurring atrial??fibrillation??, auricular fibrillation and ventricular fibrillation, and to treat?ventricular?tachycardia. It is also used to treat Wolff-Parkinson-White syndrome (WPW).
Amiodarone is usually treated as a last resort if other medications do not work, due to the severe side effects it causes, especially with continued use.
Category
Chemical class: Iodinated benzofuran derivative
Therapeutic class: Class III antiarrhythmic
Pregnancy category: D
Indications
To treat life-threatening, recurrent ventricular fibrillation and hemodynamically unstable ventricular tachycardia when these arrhythmias don’t respond to other or when patient can’t tolerate other
Adults.Loading: 800 to 1,600 mg daily in divided doses for 1 to 3 wk. Maintenance: 600 to 800 mg daily in divided doses for 1 mo; then if cardiac rhythm is stable, 400 mg daily in 1 or 2 doses. Use lowest possible dose.
IV:
Adults.Loading: 150 mg over 10 min (15 mg/ min) followed by 360 mg infused over 6 hr (1 mg/min). Maintenance: 540 mg infused over 18 hr (0.5 mg/min); then after the first 24 hr, 720 mg infused over 24 hr (0.5 mg/ min), continued up to 2 to 3 wk, as needed. Rate may be increased in first 24 hr, if needed, but initial infusion rate shouldn’t exceed 30 mg/min. Change to oral form as soon as possible. To treat breakthrough episodes of ventricular fibrillation or hemodynamically unstable ventricular tachycardia
IV:(NEXTERONE)
Adults.150 mg mixed in 100 ml D5W and infused over 10 min (15 mg/min). Route Onset Peak Duration P.O. 2 days– 1–5 mo Weeks– 3 wk months I.V. Hours– 1–3 wk Weeks– 3 days months
Mechanism of Action
Acts on cardiac cell membranes, prolonging repolarization and the refractory period and raising ventricular fibrillation threshold. Drug relaxes vascular smooth muscles, mainly in coronary circulation, and improves myocardial blood flow. It relaxes peripheral vascular smooth muscles, decreasing peripheral vascular resistance and myocardial oxygen consumption.
Incompatibilities
Amiodarone is incompatible with heparin. To prevent precipitation, don’t add amiodarone admixed with D5W to aminophylline 4 mg/ml, cefamandole nafate, cefazolin sodium, or mezlocillin sodium, and don’t mix amiodarone 3 mg/ml with sodium bicarbonate. Also, don’t use evacuated glass containers for admixing because precipitation may occur.
Contraindications
Bradycardia that causes syncope (unless pacemaker present), cardiogenic shock, hypersensitivity to amiodarone or its components, hypokalemia, hypomagnesemia, amiodarone hydrochloride 66 SA node dysfunction, secondand thirddegree AV block (unless pacemaker present)
Interactions
anticoagulants: Increased anticoagulant response and possibly serious bleeding azole antifungals, fluoroquinolones, macrolide antibiotics: Increased risk of prolonged QT interval and life-threatening arrhythmias
beta blockers: Increased serum levels of beta blockers with increased risk of AV block, hypotension, and bradycardia calcium channel blockers: Increased serum levels of these and increased risk of AV block, bradycardia, and hypotension cholestyramine, phenytoin, rifampin, St. John’s wort: Decreased amiodarone level
cimetidine: Increased amiodarone level clopidogrel: Increased risk of ineffective inhibition of platelet aggregation cyclosporine: Increased cyclosporine level dextromethorphan, methotrexate,
phenytoin: Increased serum levels of these and increased risk of toxicity if amiodarone is taken orally for more than 2 weeks digoxin: Increased serum digoxin level and risk of digitalis toxicity diltiazem, propranolol, verapamil: Increased risk of hemodynamic and electrophysiologic abnormalities disopyramide: Increased serum disopyramide level with QT prolongation and increased risk of arrhythmias fentanyl: Increased serum fentanyl level with increased risk of bradycardia, decreased cardiac output, and hypotension flecainide: Increased serum flecainide level HMG-CoA reductase inhibitors such as atorvastatin and simvastatin: Increased risk of myopathy and rhabdomyolysis hydantoins: Increased serum hydantoin level with long-term use and reduced serum amiodarone level lidocaine: Increased serum lidocaine level and risk of seizures and bradycardia loratadine, trazodone: Increased risk of QTinterval prolongation and torsades de pointes potassiumand magnesium-depleting : Increased risk of hypokalemia and hypomagnesemia procainamide: Increased serum procainamide or N-acetylprocainamide level
quinidine: Increased serum quinidine level with risk of life-threatening arrhythmias ritonavir: Increased serum amiodarone level with increased risk of cardiotoxicity
theophylline: Increased serum theophylline level; increased risk of theophylline toxicity
warfarin: Increased PT and risk of bleeding grapefruit juice: Increased amiodarone level
Side Efect
CNS: Abnormal gait, ataxia, confusion, delirium, demyelinating polyneuropathy, disorientation, dizziness, fatigue, fever, hallucinations, headache, insomnia, involuntary motor activity, lack of coordination, malaise, paresthesia, parkinsonian symptoms, peripheral neuropathy, pseudotumor cerebri, sleep disturbances, tremor
CV: Arrhythmias (including bradycardia, electromechanical dissociation, torsades de pointes, and ventricular tachycardia or fibrillation), cardiac arrest, cardiogenic shock, edema, heart failure, hypotension, vasculitis
EENT: Abnormal salivation, abnormal taste and smell, blurred vision, corneal microdeposits, dry eyes, halo vision, lens opacities, macular degeneration, optic neuritis, optic neuropathy, papilledema, permanent blindness, photophobia, scotoma
ENDO: Hyperthyroidism, hypothyroidism, syndrome of inappropriate ADH secretion, thyroid cancer
GI: Abdominal pain, anorexia, cirrhosis, constipation, diarrhea, elevated liver function test results, hepatitis, nausea, pancreatitis, vomiting
GU: Acute renal failure, decreased libido, epididymitis, impotence
HEME: Agranulocytosis, aplastic or hemolytic anemia, coagulation abnormalities, neutropenia, pancytopenia, spontaneous bruising, thrombocytopenia
MS: Muscle weakness, myopathy, rhabdomyolysis
RESP: Acute respiratory distress syndrome; bronchospasm; eosinophilic pneumonia; infiltrates that lead to dyspnea, cough, hemoptysis, hypoxia, pulmonary fibrosis, pulmonary alveolar hemorrhage, pulmonary interstitial pneumonitis, crackles, and wheezing; pleural effusion; pleuritis; pneumonia; respiratory arrest or failure
SKIN: Alopecia, bluish gray pigmentation, eczema, erythema multiforme, exfoliative dermatitis, flushing, photosensitivity, pruritus, rash, skin cancer, Stevens-Johnson syndrome, toxic epidermal necrolysis, urticaria
Other: Anaphylactic shock, angioedema
Cautions
If patient has an implantable cardiac device, have it checked, as ordered, at the start of and during amiodarone therapy because drug may affect pacing or defibrillating thresholds. Parenteral amiodarone may be diluted in D5W or normal saline solution and given in polyvinvyl chloride (PVC), polyolefin, or glass containers. Use an in-line filter during I.V. administration of amiodarone. Also use a central venous catheter whenever possible. A central venous catheter is required when infusion rate exceeds 2 mg/ml because drug may cause peripheral vein phlebitis at higher rates. Cordarone I.V. must be given by volumetric infusion pump. Monitor amiodarone I.V. infusion closely because loading doses at higher concentrations and rates may cause hepatocellular necrosis, acute renal failure, and death. Although maintenance therapy usually is needed for only up to 96 hours, infusion of up to 0.5 mg/minute may be continued for 2 to 3 weeks regardless of patient’s age, renal function, or left ventricular function.
WARNING Amiodarone may cause or worsen pulmonary disorders that may develop days to weeks after therapy and progress to respiratory failure or even death. Expect to obtain chext x-ray and pulmonary function tests before therapy starts and then chest x-ray and follow-up exams every 3 to 6 months during therapy. Monitor vital signs and oxygen level often during and after giving amiodarone. Keep emergency equipment and nearby.
WARNING Monitor continuous ECG; check for increased PR and QRS intervals, arrhythmias, and heart rate below 60 beats/min because amiodarone toxicity may cause or worsen arrhythmias. Monitor serum amiodarone level, which normally ranges from 1.0 to 2.5 mcg/ml. Assess liver enzyme and thyroid hormone levels; drug inhibits conversion of T4to T3 and may cause drug-induced hyperthyroidism, thyrotoxicosis, and new or worsened arrhythmias. If new signs of arrhythmia occur, notify prescriber at once. PATIENT SAFTY
Explain that patient will need frequent monitoring and laboratory tests during treatment. Advise patient to report swollen hands and feet, wheezing, dyspnea, cough, nausea, vomiting, dark urine, fatigue, yellow skin or sclerae, stomach pain, light-headedness, fainting, or a rapid, slow, pounding, or irregular heartbeat. Instruct patient to report abnormal bleeding or bruising. Advise patient to avoid corneal refractive laser surgery while taking drug.
Trade Name & Company Name
effect of Amiodarone in Pregnancy, Fetal Health
and Breast feeding
Pregnancy
. There are no adequate reports or well-controlled studies of amiodarone in pregnant women. The published experience is limited to fewer than 100 pregnancies. There are many alternatives to amiodarone during pregnancy. 35 Fetal Health
There are no adequate reports or well-controlled studies in human fetuses. Placental transport occurs, but studies suggest low transfer especially when the umbilical venous pressure is elevated. Amiodarone has been used in isolated instances to treat a fetal arrhythmia. Among 64 pregnancies exposed to amiodarone, 17% of neonates had hypothyroidism (10 detected at birth, 1 in utero), 18% of whom had a goiter. Hypothyroidism was transient in all, though 5 were treated short-term. Neurodevelopmental assessment of the hypothyroid infants, when carried out, revealed in some instances mild abnormalities often similar to the nonverbal learning disability syndrome. These features were also reported in some amiodarone-exposed euthyroid infants, suggesting a direct neurotoxic effect of amiodarone during fetal life. Fetal hypothyroidism has been reported in amiodarone- resistant fetal arrhythmia. Breastfeeding
Amiodarone is excreted in breast milk at concentrations high enough to have a pharmacologic effect. The reported M:P ratio ranges from 4.6 to 13, with concentrations in women ingesting 400mg/d ranging from 2.8 to 16.4mg/L. Neonatal hypothyroidism is reported.
the follwing drugs will increse Amiodarone by inhepiting cyp450
the follwing drugs will decrease Amiodarone by inhancing cyp450
trad drugs based on Amiodarone
| Gen name | Trade name | Catagory name |
| amiodarone | Cordarone | Group III antiarrhythmics |
| amiodarone | Cordarone IV | Group III antiarrhythmics |
| amiodarone | Nexterone | Group III antiarrhythmics |
| amiodarone | Pacerone | Group III antiarrhythmics |
| Amiodarone | AMIRONE 200MG TABLET | |
| Amiodarone | CORDARONE 150MG-3ML AMP | |
| Amiodarone | CORDARONE 200MG TAB | |
| Amiodarone | SEDACORON 150 MG - 3ML AMPOULES | |
| Amiodarone | SEDACORON 200MG TAB | |
other drugs from same cataogory
| Gen name | trade name | catogry |
| dofetilide | Tikosyn | Group III antiarrhythmics |
| dronedarone | Multaq | Group III antiarrhythmics |
| amiodarone | Cordarone | Group III antiarrhythmics |
| amiodarone | Pacerone | Group III antiarrhythmics |
| sotalol | Betapace AF | Group III antiarrhythmics |
| sotalol | Betapace | Group III antiarrhythmics |
| sotalol | Sotylize | Group III antiarrhythmics |
| amiodarone | Nexterone | Group III antiarrhythmics |
| amiodarone | Cordarone IV | Group III antiarrhythmics |
| sotalol | Sorine | Group III antiarrhythmics |
| ibutilide | Corvert | Group III antiarrhythmics |