statin-on-statin
3 interactions related to statin-on-statin
rosuvastatin + red yeast rice
Red yeast rice contains monacolin K, a compound chemically identical to a statin, so taking it alongside rosuvastatin stacks a second statin-like HMG-CoA reductase inhibitor on top of the prescription statin. Because rosuvastatin is not broken down by the CYP3A4 enzyme, there is no enzyme-based (pharmacokinetic) interaction; the concern is purely additive statin-class exposure. This modestly raises the combined potential for statin-type muscle injury (myopathy, and rarely rhabdomyolysis) and liver injury beyond either agent alone. The added statin burden is usually small because red yeast rice's monacolin content is typically low, highly variable, and not shown on the label, but unregulated high-monacolin products can carry a more meaningful statin-like load.
lovastatin + red yeast rice
Red yeast rice contains monacolin K, which is chemically identical to the statin lovastatin. Taking red yeast rice together with prescription lovastatin means taking the same statin twice, adding to HMG-CoA reductase inhibition and raising the risk of muscle injury (including rhabdomyolysis) and liver harm. Because the amount of monacolin K in red yeast rice is variable and usually not stated on the label, the added statin exposure is unpredictable and stacks on top of an already-active prescription dose.
pravastatin + red yeast rice
Red yeast rice contains monacolin K, a compound chemically identical to the statin lovastatin. Taking it alongside pravastatin means two HMG-CoA reductase inhibitors are active at the same time, so their cholesterol-lowering statin effect and their potential for muscle injury (muscle pain, and rarely rhabdomyolysis) add together. Because pravastatin is water-soluble and is not broken down by the CYP3A4 enzyme, this is not a metabolic (drug-processing) interaction — it is simply the additive effect of stacking two statin-type ingredients, made harder to gauge by red yeast rice's variable, unlabeled monacolin content.