"The supplement does not provide a standardized dosage ... [which is] very dangerous. You don't know exactly how much statin you are getting," said Dr. Steve Nissen, chairman of the department of cardiovascular medicine at the Cleveland Clinic Foundation.
"Why would any sane human take dietary supplement containing an uncontrolled dosage of a statin, when the purified form of the statin is available as an inexpensive generic?" he added.
Unlike prescription drugs, herbal extracts such as the red yeast pills do not undergo any formal safety evaluation. Because of the risk that some off-brands of red yeast extract may contain an unsafe dose of lovastatin or even some other unknown contaminants, many doctors remain wary in recommending the extract to their heart patients.
The U.S. Food and Drug Administration even released a warning to consumers in August 2007 not to buy or eat three specific red yeast rice products promoted and sold on Web sites. The FDA found that since these products contained the same active ingredient as a prescription medicine, they are unauthorized to be sold over-the-counter or online.
"We do not have a reliable product at this time containing red rice yeast in the U.S. dietary supplement market," said Dr. Nicole Nisly, director of the complementary medicine program at the University of Iowa. Nisly said that for this reason, she would never recommend that one of her patients try red yeast rice extract to lower cholesterol.
But some experts said that as long as patients seek out "reliable" brands of red yeast rice extract, such as those sold in grocery stores or reputable nutritional supplement chains, they can safely lower their cholesterol just as well as they would be taking a statin drug.
Dr. Daniel Edmundowicz, director of the preventive cardiology operations at the University of Pittsburgh's Cardiovascular Institute, said that he often recommends the red yeast rice extract to his heart patients who are reluctant to take prescription drugs or are unable to tolerate statins.
"The end justifies the means here," Edmundowicz said. "For some of my patients, I'd rather get them to their cholesterol goal than see them avoid medication altogether."
However, Edmundowicz admitted that it's still a challenge to make sure that patients opting for this extract over the traditional statin are choosing a reliable product that doesn't contain contaminants.
"The biggest challenge about recommending the extract to my patients is figuring out where they get it from and what's in it," Edmundowicz said. "What we'll do is tell patients to go with the nationally known brands -- for instance, something bought at GNC."
"I tell them stay away from the Internet and vitamin houses they've never heard of," Edmundowicz added.