Harmful Side Effects Of Red Yeast Rice

Red yeast rice comes from growing Monascus purpureus yeast on red rice. Used as a Chinese medicine as well as a dietary staple, red yeast rice contains compounds that lower cholesterol, including monacolin K, a compound similar to lovastatin, marketed as a prescription medication. In the United States, red yeast rice that contains lovastatin cannot be sold according to U.S. Food and Drug Administration guidelines. The harmful effects of red yeast rice are the same potential side effects of lovastatin, plus several side effects specific to red yeast rice. Check with your doctor before taking this supplement.

Liver Problems

Statin medications can worsen or increase the risk of developing liver damage. Since red yeast rice often contains a statin medication, people with liver problems or who are at risk for developing liver problems should not take this supplement.

Muscle Problems

Like other statin type medications, red yeast rice can cause muscle aches and pain. In severe cases, rhabdomyolysis, severe muscle pain caused by muscle breakdown that can lead to kidney failure, can occur. Higher doses of monacolin K found in red yeast rice are more likely to cause the complication. The amount of lovastatin varies considerably from one brand of red yeast rice to another, with 100-fold variation found in 10 samples, according to ConsumerLab president Tod Cooperman. Signs of rhabdomyolisis include muscle weakness or tenderness, fever, tiredness and possibly tea-colored urine or decreased urination. Call your doctor immediately if you experience these symptoms.

Citrinin Contamination

A 2001 study of red yeast rice, reported in the "Journal of Alternative and Complementary Medicine" by the UCLA School of Human Nutrition, looked at the contents of red yeast rice. Lead author D. Heber reported that seven out of nine samples were contaminated with citrinin, a potentially toxic product produced during the fermentation process. ConsumerLab tested 10 samples; four contained citrinin. Side effects of citrinin ingestion in animals vary by species but can include poor growth, immunosuppression, increased bruising and increased susceptibility to infections.

Increased Bleeding

Red yeast rice may cause increased bleeding in people taking anti-coagulants or in people with bleeding disorders. Medications may need to be adjusted if you take red yeast rice. Do not take this supplement without your doctor's approval if you take blood thinners.

Allergic Reactions

Allergic reactions to red yeast rice can cause serious, life-threatening reactions. Hives, rash, shortness of breath, difficulty breathing, throat swelling, facial swelling, low blood pressure or circulatory collapse can occur. Seek immediate medical care if these symptoms occur.