Monitor patients for QTc prolongation during infusion with amiodarone. Preclinical studies in rodents have not shown any effect on the duration of gestation or on parturition.Amiodarone and one of its major metabolites, desethylamiodarone (DEA), are excreted in human milk, suggesting that breastfeeding could expose the nursing infant to a significant dose of the drug. Effects of an inadvertent overdose of intravenous amiodarone include hypotension, cardiogenic shock, bradycardia, AV block, and hepatotoxicity. Perform an ophthalmic examination if symptoms of visual impairment appear, such as changes in visual acuity and decreases in peripheral vision. Monitor the initial rate of infusion closely and do not exceed the recommended rate [see Dosage and Administration (2)].In some cases, hypotension may be refractory and result in a fatal outcome [see Adverse Reactions (6.2)].In 90 (4.9%) of 1836 patients in clinical trials, drug-related bradycardia that was not dose-related occurred while they were receiving intravenous amiodarone for life-threatening VT/VF. A placebo-controlled study of intravenous amiodarone (300 mg over 2 hours followed by 1200 mg/day) in post-coronary artery bypass graft patients with supraventricular and 2- to 3-consecutive-beat ventricular arrhythmias showed a reduction in arrhythmias from 12 hours on. The risk of exposing the infant to amiodarone must be weighed against the potential benefit of arrhythmia suppression in the mother. Embryotoxicity (as manifested by fewer full-term fetuses and increased resorptions with concomitantly lower litter weights) occurred at dosages of 10 mg/kg and above. Correct hypokalemia or hypomagnesemia whenever possible before initiating ... after the end of the infusion. Discuss the symptoms of hypo- and hyper-thyroidism, particularly if patients will be transitioned to oral amiodarone.The easiest way to lookup drug information, identify pills, check interactions and set up your own personal medication records. Manage hypothyroidism by reducing the amiodarone dose and considering the need for thyroid hormone supplement.
Amiodarone must be delivered by a volumetric infusion pump.Administer amiodarone, whenever possible, through a central venous catheter dedicated to that purpose. Amiodarone is metabolized to DEA by the cytochrome P450 enzyme group, specifically cytochromes CYP3A and CYP2C8. DEA's precise role and contribution to the antiarrhythmic activity of oral amiodarone are not certain.
In general, start at the low end of the dosing range in the elderly to reflect the greater frequency of decreased hepatic, renal, or cardiac function, and concomitant disease or other drug therapy.There have been cases, some fatal, of amiodarone overdose.
The action of antithyroid drugs may be especially delayed in amiodarone-induced thyrotoxicosis because of substantial quantities of preformed thyroid hormones stored in the gland. Perform regular ophthalmic examination, including fundoscopy and slit-lamp examination, during administration of amiodarone.There has been limited experience in patients receiving intravenous amiodarone for longer than 3 weeks. Pulmonary toxicity is a well-recognized complication of long-term amiodarone use (see package insert for oral amiodarone).Cases of optic neuropathy and optic neuritis, usually resulting in visual impairment, have been reported in patients treated with oral amiodarone. The CYP3A isoenzyme is present in both the liver and intestintes. Normal subjects over 65 years of age show lower clearances (about 100 mL/hr/kg) than younger subjects (about 150 mL/hr/kg) and an increase in t½ from about 20 to 47 days.Effect of Gender: Pharmacokinetics of amiodarone and DEA are similar in males and females.Renal Impairment: Renal disease does not influence the pharmacokinetics of amiodarone or DEA.Hepatic Impairment: After a single dose of intravenous amiodarone to cirrhotic patients, significantly lower Cmax and average concentration values are seen for DEA, but mean amiodarone levels are unchanged.Cardiac Disease: In patients with severe left ventricular dysfunction, the pharmacokinetics of amiodarone are not significantly altered but the terminal elimination t½ of DEA is prolonged.Although no dosage adjustment for patients with renal, hepatic, or cardiac abnormalities has been defined during chronic treatment with oral amiodarone, close clinical monitoring is prudent for elderly patients and those with severe left ventricular dysfunction.There is no established relationship between drug concentration and therapeutic response for short-term intravenous use.13.1 Carcinogenesis, Mutagenesis, Impairment of FertilityNo carcinogenicity studies were conducted with intravenous administration of amiodarone. Therefore, amiodarone has the potential for interactions with drugs or substances that may be substrates, inhibitors or inducers of CYP3A. In these studies, patients with at least two episodes of VF or hemodynamically unstable VT in the preceding 24 hours were randomly assigned to receive doses of approximately 125 or 1000 mg over the first 24 hours, an 8-fold difference. Advise the mother to discontinue nursing.The safety and effectiveness of amiodarone in pediatric patients have not been established; therefore, the use of amiodarone in pediatric patients is not recommended. You should avoid consuming grapefruits and grapefruit juice while taking amiodarone.