Amiodarone is an antiarrhythmic drug used to treat life-threatening irregular heartbeats caused by ventricular tachycardia and ventricular fibrillation.

The drug was initially approved by the U.S. Food and Drug Administration in 1985. However, the agency has warned that the drug is only to be prescribed to patients as a last resort and that other treatment options should be exhausted before turning to amiodarone.

The long-term side effects of amiodarone may lead to life-threatening complications for some patients.

What Are the Long-Term Side Effects of Amiodarone?

Amiodarone is a very toxic drug, according to Healthline. Long term use of amiodarone can lead to toxicity in several organs of the body, including pulmonary toxicity. Although the drug may be necessary for patients with life-threatening heart arrhythmias, the long-term side effects of amiodarone may be just as dangerous.

Side effects of amiodarone may include:

• Halo vision, caused by deposits formed on the cornea. This vision change turns bright lights blurry and gives the impression of false rings around them.
• Blue-grey skin discolorations
• Abnormally low blood pressure
• Skin sensitivity to sunlight
• An increased risk of sunburn
• Peripheral neuropathy
• Neonatal hypothyroidism
• Optic neuritis
• Blindness or vision loss
• Acid reflux disorder
• Interstitial pneumonitis
• Neurotoxicity
• Liver toxicity
• Lung stiffening, lung fibrosis, or lung toxicity, which may be fatal
• Thyroid disorders, including hypothyroidism and hyperthyroidism
• Death

The severe side effects associated with amiodarone has resulted in strict prescribing recommendations. The drug is typically only prescribed as a last resort in patients who would die without it.

What is Amiodarone Toxicity?

According to Helio, the term “amiodarone toxicity” typically refers to the toxicity of the lungs, thyroid, or liver caused by treatment with amiodarone.

Pulmonary toxicity is the most common type of toxicity caused by amiodarone and can be the most deadly. Between one and five percent of patients taking 200 mg of amiodarone every day will develop pulmonary toxicity. Up to 15 percent of patients taking 400 mg or more of amiodarone every day have been shown to develop the condition.

Amiodarone pulmonary toxicity may manifest as chronic interstitial pneumonitis, a rare disease affecting the tissues which support the lungs’ air sacs. Lung toxicity can also result in symptoms mimicking pulmonary fibrosis a condition characterized by chronic inflammation of the lung tissue leading to scarring.

Amiodarone toxicity may also result in thyroid problems, including hyperthyroidism or hypothyroidism. Hyperthyroidism involves too much of the thyroid hormone thyroxine while hypothyroidism causes low levels of this hormone. Between three and five percent of amiodarone patients develop hyperthyroidism while around five percent of patients develop hypothyroidism.

Liver toxicity is also a potential side effect of amiodarone, with around 25 percent of patients experiencing elevated levels of liver enzymes. If left untreated, this can result in liver failure.

In most cases, discontinuing amiodarone will fix the toxicity and other side effects of the drug. However, lung toxicity may need steroid treatment to resolve and thyroid problems may also require long term treatment.

Due to the storage of the built-up drug in the tissues, weaning off of amiodarone is also a slow process, as the drug stays in the body for much longer after the patient stops taking it. Additionally, it may take weeks or months for the side effects of amiodarone to develop and be noticed by the patient.

How Does Amiodarone Work?

The Mayo Clinic explains that amiodarone helps to regulate heart rhythm by cutting off the electrical signals in the heart that cause irregular beating. By slowing nerve impulses in the heart tissue, it helps to stop life-threatening arrhythmias and irregular beats. If arrhythmias are not treated, they may lead to dangerous health consequences, including stroke or cardiac arrest.

Amiodarone has many unique characteristics. Most drugs are circulated by the body’s bloodstream until they are excreted or metabolized. Amiodarone is different and is stored in the body’s tissues. It also needs to build up before the effects of the medication will be felt by the patient. Patients often need to take amiodarone consistently for several weeks before the drug will begin to work.

If you have been prescribed amiodarone for the treatment of a heart condition or arrhythmia and have suffered from one of the serious health side effects, legal help may be available to you. Victims who have been seriously harmed by side effects of the drug may be eligible to hire an attorney and file a class action lawsuit regarding these side effects. Victims who file lawsuits may be able to collect compensation for pain and suffering, medical expenses, injuries, loss of income or earning capacity, and other costs associated with their amiodarone side effects.