Red yeast rice products – legitimate concerns?
High blood lipid levels together with high blood pressure and diabetes are among the highest risks for coronary heart disease. In particular, an elevated cholesterol level promotes the progression of atherosclerotic processes. Therapeutically, it is mainly statins which are used to lower cholesterol levels. The use of dietary supplements made of red yeast rice, also called red fermented rice or red mold rice, as an alternative is currently the focus of a critical consideration of the ingredient Monakolin K.
Proprietary medicinal products based on the Statin group of drugs inhibit the key enzyme that converts the HMG-CoA produced by cholesterol biosynthesis into mevalonate. Due to reduced cholesterol synthesis, LDL cholesterol is increasingly broken down and HDL is increasingly formed. In addition, other pleiotropic effects, such as anti-inflammatory, antioxidant or direct vascular effects, are described in the literature.
The substances available on the market are considerably different in potency as well as side effects and interactions. The most significant side effects range from mild muscle pain up to myopathy with an increase in creatine kinase. The most dangerous complication is the extremely rare rhabdomyolysis which is a disintegration of striated muscle.
It should be noted in this context, however, that in view of the millions of prescriptions of these drugs, they are generally considered to be a very safe class of drugs.
Red yeast rice: Similar side effects
Alternatively, red yeast rice is offered in the form of dietary supplements or supplemented balanced diets. Red yeast rice is not a separate rice variety, but produced by the fermentation of ordinary rice with a certain mold fungi of the Monascus genus. During the fermentation, red dyes and various other potentially pharmacologically and toxicologically active ingredients are produced. The effective ingredient in these products is monacolin K which is identical to the drug Lovastatin.
Accordingly, in contrast to partially false medial representations, when taking products with red yeast rice there is a comparable effect, even if significantly reduced, and the potential for similar side effects and interactions as with using statins as drugs is to be assumed.
The prodrug Lovastatin, after gastrointestinal absorption and hydrolysis into hydroxyacid, is metabolised mainly in the liver by CYP-3A4. Hence, there are numerous interactions.
Strong CYP-3A4 inhibitors, in particular, can increase the risk of myopathy by strongly increasing the inhibitory activity of the HMG-CoA reductase in plasma during Lovastatin or red yeast rice therapy. These inhibitors include, for example, Cyclosporin, Itraconazole, Clarithromycin, Verapamil, Aprepitant, Amiodarone as well as HIV protease inhibitors such as Ritonavir and other cholesterol lowering agents such as Fibrates.
If grapefruit juice, known for interactions, is consumed in large amounts, there may also be a significant increase in HMG-CoA reductase inhibitory activity. Furthermore, there is clear evidence that Lovastatin inhibits the membrane transport protein P-glycoprotein, which plays an important role in the detoxification of drugs. This efflux transporter, which is predominantly found in excretory tissues, actively transports not only endogenous substances, such as steroids and cytokines, but also potentially toxic xenobiotics, out of cells. The inhibitory effect of Monacolin K (Lovastatin) on this transporter can thus also significantly influence the bioavailability and the distribution of drugs.
There is also evidence in the literature of the widely varying ratio of Monacolin K and Monacolin K acid in various products. This situation represents an additional factor of uncertainty because Monacolin K acid, which is the active form of Monacolin K, is much more readily absorbed. Therefore, the bioavailability of these products is difficult to estimate because the biological effect is not determined solely by the content of Manokolin K.
Misrepresentations in the media can suggest to patients that an adequate intake of red yeast rice products could provide sufficient treatment. However, this is grossly negligent, especially in the secondary prophylaxis of cardiovascular events which requires sufficient efficacy levels of a potent statin for therapeutic success.
One company went so far as to recommend the treatment of elevated cholesterol levels with red yeast rice products to patients who cannot tolerate statin therapy!
It should also be noted that dietary supplements are often considered by consumers to be less dangerous. This can be very deceptive in this case. Statins, and thus also red yeast rice products, are generally contraindicated during pregnancy and lactation due to their teratogenicity observed in animal experiments.
The literature also points to a lack of standardisation of monacolin levels as well as to the detection of nephrotoxic mycotoxin citrin. Another major factor of uncertainty is the taking of the drugs outside of medical control and the fact that there is no systematic recording of adverse effects, as required by law for authorised drugs.
Taking red yeast rice products and statins at the same time can easily lead to overdoses and side effects. Incidentally, Lovastatin should also be used with caution in patients who consume significant amounts of alcohol and/or have a history of liver disease.
It is recommended that red yeast rice products are only given out with appropriate warnings as they have the same clinically relevant risk potential as statins.
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