According to the American Heart Association, high blood cholesterol is a major risk factor for coronary heart disease and stroke. The medical consensus is that total cholesterol count over 200 mg/dL of blood is not healthy and warrants possible pharmaceutical care. Statins are the primary type of cholesterol lowering drugs, which work by blocking a substance the body needs to make cholesterol. Statins include well-known medications such as Lipitor, Zocor and Crestor, all of which cause a variety of side effects.
Muscle Side Effects
According to MayoClinic.com, all statin drugs can cause muscle pain, weakness, tenderness and potentially, rhabdomyolysis, which is a condition that rapidly breaks down muscle fibers. Rhabdomyolysis causes a massive release of protein, called myoglobin, into the bloodstream, which can overwhelm the filtering action of the kidneys. The kidneys can subsequently become clogged, leading to acute renal failure. Certain drugs, when taken in conjunction with statins, can greatly increase the risk of rhabdomyolysis, such as erythromycin, antifungal medications, cyclosporine and niacin.
The risk of muscle injury while on statin drugs is dose dependent and dramatically increases at doses of 80 mg or more daily. Some statin drugs, such as Zocor, can cause creatine kinase levels in the blood to increase 10 times above normal, which is another indicator of muscle damage, according to Drugs.com. Predisposing risk factors for muscle pain and rhabdomyolysis include age older than 65 years, untreated hypothyroidism and existing kidney disease.
Liver Side Effects
According to the "Compendium of Pharmaceuticals and Specialties," the use of statin drugs, such as Lipitor and Zocor, can cause increases in liver enzymes, which is an indication of liver damage. Discontinuing statin use immediately often reverses the liver problem, but if left unchecked, increased liver enzymes can lead to permanent liver damage. Visible signs of liver damage include jaundice, which is yellowing of the eyes and skin from an accumulation of unmetabolized bilirubin.
Often, increased liver enzymes do not produce physical symptoms or signs, so patients prescribed statin drugs are recommended to have blood tests to establish normal liver enzyme levels before initiating use and again six weeks later for comparison. If liver enzymes are only mildly increased after six weeks, then continuation with the statin drug is recommended. Beyond that, the prescribing doctor may recommend yearly blood tests for monitoring purposes. Niacin also increases the risk of liver dysfunction while on statin drugs.
Common, Less Serious Side Effects
According to Drugs.com, the most commonly reported side effects from statin drug use, aside from muscle issues, are upper respiratory tract infections, headaches, abdominal pain, constipation, diarrhea, nausea, joint aches, hives and skin rash.
References
- American Heart Association: Cholesterol Levels
- MayoClinic.com: Statin Drug Side Effects
- Drugs.com: Zocor Side Effects
- "Compendium of Pharmaceuticals and Specialties"; Canadian Pharmacists Association; 2010
