What Are the Negative Effects of Vytorin?

Vytorin is a prescription medication combining Zocor (simvastatin) and Zetia (ezetimibe), designed to lower high cholesterol. Statin drugs, such as simvastatin, inhibit a liver enzyme necessary for producing cholesterol, while ezetimibe decreases cholesterol absorption in the intestines. Distributed by Merck and Co., Inc. and the Schering-Plough Corporation, the drug was approved by the U.S. Food and Drug Administration in 2004. Most of the side effects are associated with the statin component of Vytorin.

Side Effects

• The most common side effects of Vytorin include headache, nausea, vomiting, diarrhea, muscle pain and elevated liver enzymes. These usually are caused by Zocor, as even the most common side effects of Zetia affected fewer than 4 percent of participants in clinical trials. Other side effects associated with Zetia include dizziness, back pain, joint pain and fatigue. A very large number of uncommon side effects also are linked to Zocor, including insomnia, anxiety, depression, memory loss, altered taste, blurred vision and rash. Vytorin also can cause severe allergic reactions.

Myopathy

• Vytorin can cause a rare negative effect of drug-induced myopathy, an abnormal muscle condition. Symptoms are muscle weakness and obvious muscle pain, along with fatigue. This negative effect can appear anywhere from days to months after beginning Vytorin use and is usually reversible if the person stops taking the drug.

Rhabdomyolysis

• More rarely, the muscle problems caused by Vytorin can develop into a very severe condition called rhabdomyolysis. This disorder involves skeletal muscle breakdown, which releases proteins called myoglobin into the bloodstream. Myoglobin can obstruct kidneys, causing kidney damage and even kidney failure.

Liver Issues

• People with liver problems such as hepatitis or cirrhosis should not use Vytorin, because statins can cause elevated liver enzymes. Also, people who consume large amounts of alcohol may not be able to take Vytorin. For people with normal liver function before beginning Vytorin, liver enzymes usually return to normal when the medication use is discontinued.

Additional Concerns

• Because a developing fetus and a developing baby both need cholesterol for growth, pregnant women and those who are breastfeeding should not take Vytorin. Also, people taking other drugs may not be able to take Vytorin, because it interacts negatively with many medications. These include anticoagulants, antibiotics, antifungals, high blood pressure medications and immune system suppressants.

Expert Insight

• A large study released by Merck and Schering-Plough in 2007 showed that the average level of low-density lipoprotein (LDL) cholesterol, the so-called bad cholesterol, decreased by 58 percent in the participants taking Vytorin compared with a 41 percent decrease in those taking only Zocor. However, Vytorin worked no better than Zocor alone at preventing fatty plaque buildup in neck arteries, an indication that it would not be more effective at preventing heart attack or stroke. Of 720 patients total, the Vytorin group had two deaths and three nonfatal heart attacks, while the Zocor group had one death and two nonfatal heart attacks, a statistically-insignificant difference.