Simvastatin belongs to the statin class of cholesterol-lowering medications. These drugs interfere with the body's ability to make new cholesterol, which then reduces cholesterol levels in the blood. Although these medications are very effective at lowering cholesterol levels and can also reverse the effects of atherosclerosis, statin medications can cause certain serious side effects.
Gastrointestinal
The use of simvastatin can upset the digestive tract, Drugs.com explains. This can lead to stomach pain, nausea, constipation and diarrhea. These side effects are generally mild and do not require medical attention unless they become a significant source of discomfort.
Neurological/Psychiatric
Simvastatin is known to cause certain neurological problems, eMedTV notes. These include a headache and vertigo. Patients taking simvastatin may also experience more serious problems which include insomnia, anxiety, depression and memory loss. These side effects may require additional medical treatment.
Increased Infections
There is also some evidence that simvastatin can impair the immune system, RxList explains. Patients taking simvastatin may have an increased risk of developing infections of the upper respiratory system and the urinary tract.
Allergic
Simvastatin, like many pharmaceutical medications, can generate an allergic response in susceptible patients. The most serious type of allergic reaction is known as anaphylaxis, in which the throat begins to swell. This can make breathing and swallowing difficult and can also result in hoarseness and tightness in the chest. Less serious symptoms of an allergic reaction include swelling of the lips, face and extremities, as well as an itchy rash with hives.
Hepatitis
In clinical testing, simvastatin was found to elevate the amounts of certain liver enzymes, such as alkaline phosphatase, in the blood, RxList explains. These increased enzyme levels are typically a signal that the liver has become inflamed, which can result in liver damage or failure. Consequently, patients taking simvastatin should contact their doctors if they experience yellowing of the skin or whites of the eyes, sudden problems with bleeding/bruising or unusually dark urine.
Muscle/Joint Pain
Simvastatin can also result in aching muscles and joints. For some patients, this may be a sign of a more serious side effect known as rhabdomyolysis, a condition in which muscle cells within the body are being rapidly broken down. Not only does this damage and weaken the muscles, it also results in the release of large amounts of proteins and other substances into the blood. Because the kidneys have to filter out these substances, rhabdomyolysis can result in kidney damage and failure, requiring a kidney transplant or dialysis.
