The efficacy of dietary supplements is usually questionable because of the lack of controlled clinical trials supporting their use. Two randomized, double-blind, placebo-controlled trials7,8
and an open-label trial9
demonstrated that red yeast rice might be effective in lowering LDL-C levels.
Lu et al. further demonstrated that red yeast rice might be able to reduce cardiac events and provide positive effects on cardiovascular outcomes in a fashion similar to that of prescription statin therapy.7
Although larger-scale trials are necessary to confirm these findings, red yeast rice seems promising in the treatment of hyperlipidemia. Such efficacy data influence patients to try natural remedies before using more common prescription drug therapies. The vast amount of data demonstrating the benefits of statin therapy in cardiovascular disease supports its continued use, but practitioners should be aware of alternative therapies being used by their patients.
Unlike prescription drugs, dietary supplements have not traditionally undergone extensive testing by the FDA. Without adequate testing, dietary supplements are not guaranteed to contain the quantity or quality of ingredients stated on the product label. As shown by Heber et al., red yeast rice is no exception.13
Each of the nine products tested had different monacolin levels. Supplements with a lower monacolin content would be less effective in lowering cholesterol.
Seven of the tested samples contained citrinin, a mycotoxin produced by a variety of fungi in the production of foods intended for human consumption such as grain, cheese, and red pigments. Citrinin is a nephrotoxin in all animal species tested, but its acute toxicity varies.14
Citrinin is genotoxic at high concentrations in cultured human lymphocytes; therefore, its concentration in supplements should be minimal.15
Inconsistencies such as these led the FDA to require current good manufacturing practices (CGMPs) for dietary supplements.16
Final CGMPs were expected to become effective in June 2008 for large companies and are to be implemented in June 2009 for companies with fewer than 500 employees and in June 2010 for companies with fewer than 20 employees. Under this ruling, all domestic and foreign supplements must be processed in a consistent manner and to meet quality standards. To demonstrate quality and consistency, tests will be performed on all supplements to ensure their identity, purity, strength, and composition.
Statin drugs such as Merck’s Mevacor (lovastatin) are associated with various side effects such as headache, dizziness, rash, upset stomach, and hepatic dysfunction. The most common adverse effect is muscle weakness, which can be a sign of more serious myopathy or, in rare cases, rhabdomyolysis.17
Double-blind, controlled clinical trials have demonstrated that red yeast rice is effective and well tolerated in a wide range of patients;7,8
however, case reports have linked it to muscular myopathy and rhabdomyolysis. In three cases described here,4,10,11
red yeast rice caused or exacerbated myopathy marked by elevated serum CK levels. Rhabdomyolysis, the most severe adverse effect associated with statins, occurred in a renal transplant patient who used red yeast rice while concomitantly taking cyclosporine.12
Although the more reliable controlled trials showed no need for safety concerns, case reports warn of the possibility of adverse effects with wider use. These reports should not be ignored for patients who are taking red yeast rice as an alternative to common prescription statins.
Lovastatin as a prescription drug is contraindicated in pregnancy and is a Category X agent. This labeling is a main reason for the FDA’s rejection of the application submitted by Merck to sell lovastatin over the counter.18
Red yeast rice, when used by pregnant women, places the fetus at unnecessary risk of central nervous system defects during the first trimester. Although red yeast rice contains a lower dose of lovastatin compared with the FDA-approved product, the risk posed may be similar.