Pacerone (amiodarone) is a medication that is used to treat irregular heart rhythm. Unfortunately, it has been identified as a risk factor for severe, life-threatening liver damage, lung damage, skin reactions, blindness, and muscle injuries (also known as “myopathy”) which can progress to life-threatening rhabdomyolysis, kidney failure, and death. The FDA has warned that the risk of muscle injury increases when Pacerone is combined with simvastatin (Zocor and other brand-names), especially at high doses.
Pacerone (amiodarone) is a brand-name of the generic drug amiodarone that is manufactured by Upsher-Smith Laboratories. It has been prescribed to millions of people to help treat irregular heart rhythm in the lower chambers of the heart (ventricles), also known as ventricular arrhythmias.
Serious Side Effects of Pacerone
According to the FDA, “Amiodarone may cause potentially fatal toxicities, including pulmonary toxicity, hepatic injury, and worsened arrhythmia.” The FDA warns that it should “only be used to treat adults with life-threatening ventricular arrhythmias when other treatments are ineffective or have not been tolerated.”
Some of the most serious side effects of Pacerone occur when the medication is combined with simvastatin (Zocor). In clinical trials, reported side effects of Pacerone include:
- Skin reactions (light-sensitivity, Toxic Epidermal Necrolysis)
- Lung damage (chronic pulmonary fibrosis)
- Muscle injury, myopathy, rhabdomyolysis (especially when Pacerone is combined with simvastatin)
- Liver damage
- High blood pressure
- Irregular heart rhythm
- And more
Pacerone and Lung Disease
According to the FDA Drug Safety Communication:
“The most important of these is pulmonary toxicity (hypersensitivity pneumonitis or interstitial/alveolar pneumonitis). This has occurred as clinically manifest disease at rates as high as 17 percent in some series of patients with ventricular arrhythmias given doses of around 400 mg daily, as abnormal diffusion capacity without symptoms in a much higher percentage of patients. Pulmonary toxicity is fatal about 10 percent of the time.”
Pacerone and Toxic Epidermal Necrolysis (TEN)
Toxic Epidermal Necrolysis (TEN) is a rare but severe skin reaction that causes large portions of the epidermis (the uppermost layer of skin) to detach from the layers of skin below.
The drug reaction is most severe in the mucous membranes, such as the eyes, mouth, and vagina. The patient may require feeding with a gastric tube directly into the stomach. The eyes can be severely damaged, and the condition may cause blindness.
FDA Warning for Pacerone / Simvastatin Combination
On December 15, 2011, the U.S. Food and Drug Administration (FDA) published a Safety Communication regarding the risk of muscle injury when Pacerone (amiodarone) is combined with simvastatin.
According to the FDA, people taking both medications should limit the dose of simvastatin to 20-mg per day. The FDA had previously recommended a limit of 10-mg in June 2011, but they reconsidered that recommendation.
Pacerone / Simvastatin and Muscle Injuries
According to the FDA, combining Pacerone (amiodarone) and simvastatin increases the risk of muscle injury, also known as myopathy. Symptoms of this disease include muscle pain, tenderness, and cramping, which may be an indication that muscle fibers are breaking down. If myopathy is not treated, it can grow progressively worse and become rhabdomyolysis, a life-threatening disease in which damaged muscle release a protein (called myoglobin) that clogs the kidneys and causes kidney damage.
Symptoms of rhabdomyolysis:
- Muscle pain, tenderness, swelling, cramping
- Muscle weakness (especially in the arms or legs)
- Dark or cola-colored urine
- Decreased urine output
- Increased levels of creatine kinase enzyme in the bloodstream
- Cardiac arrhythmia
- Nausea, vomiting
- And more