Is it safe to take losartan with red yeast rice supplements?

Taking losartan together with red yeast rice is generally not known to cause a direct, specific drug–drug interaction, but there are important safety considerations you should weigh before combining them. Red yeast rice contains natural statin-like compounds (notably monacolin K, which is chemically identical to lovastatin), so its side-effect profile and interaction risks can mirror prescription statins; meanwhile, losartan has its own safety profile but does not typically interact with statins. ^{[1] [2]} That means many people may take them together without a pharmacokinetic conflict, yet you could still face risks related to red yeast rice itself, such as muscle problems or liver effects, and quality variability across supplements. ^{[3] [4]}

What red yeast rice does

• Red yeast rice supplements can lower LDL (“bad”) cholesterol because they may contain monacolin K, the same active ingredient as the statin lovastatin. ^{[5] [3]}
• Because of this, red yeast rice can cause statin-like side effects: muscle pain or weakness, rare but serious muscle injury (myopathy/rhabdomyolysis), and liver enzyme elevations. ^{[1] [6]}
• Potency and purity vary widely between brands, and some products may contain very little active ingredient or a contaminant called citrinin (a potential kidney toxin). ^{[3] [7]}

What losartan does

• Losartan (an angiotensin II receptor blocker, ARB) is used for blood pressure and kidney/heart protection, and it does not typically interact with statins or statin-like agents. ^[8]
• Key losartan interaction cautions focus on medicines or supplements that raise potassium (hyperkalemia risk) and on lithium; myopathy with ARBs is rare and not a typical interaction mechanism with statins. ^{[8] [9]}

Known interaction signals between the two

• There is no well-documented, direct interaction between losartan and statins or statin-like compounds from red yeast rice in standard references. This suggests they can often be co‑used when clinically appropriate. ^[8]
• However, red yeast rice can interact with other agents (for example, strong CYP3A4 inhibitors, gemfibrozil, high-dose niacin), which can increase muscle or liver risks; these are important if you take additional medicines besides losartan. ^{[6] [10]}
• Some red yeast rice extracts can inhibit certain drug‑metabolizing enzymes and P‑glycoprotein in lab studies, though clinical relevance appears limited; still, this underscores variability and the need for caution with polypharmacy. ^{[11] [10]}

Practical safety tips if you consider combining them

• Start only if you truly need cholesterol lowering and have discussed alternatives with your clinician, since red yeast rice behaves like a statin. ^[1]
• Avoid alcohol excess and grapefruit juice while on red yeast rice, as these can increase liver or muscle side effects. ^[12]
• Do not combine red yeast rice with prescription statins, gemfibrozil, or high‑dose niacin unless specifically advised, due to additive muscle risk. ^{[6] [10]}
• Choose reputable, standardized products that test for monacolin K content and citrinin; many over‑the‑counter products are inconsistent. ^{[3] [7]}
• Monitor for symptoms: new muscle pain, weakness, dark urine, unusual fatigue, abdominal pain, or jaundice warrant stopping the supplement and seeking care. ^{[1] [4]}
• Ask your clinician about baseline and follow‑up liver enzymes (ALT/AST) and, if symptomatic, a CK (creatine kinase) test; this is similar to statin monitoring. ^[1]
• Keep an eye on your full medication list; if you add any CYP3A4 inhibitors (for example, certain antibiotics like erythromycin), risk from red yeast rice may increase. ^[12]

When it may not be a good idea

• If you already take a statin or have a history of statin intolerance or muscle/liver problems, adding red yeast rice could increase the chance of side effects. ^{[6] [1]}
• If you are pregnant, breastfeeding, have active liver disease, or drink heavily, red yeast rice would generally be avoided. ^[1]
• If your only goal is blood pressure control, red yeast rice does not meaningfully lower blood pressure and is not a substitute for antihypertensive treatment. ^[13]

Bottom line

• There isn’t a clear, direct interaction between losartan and red yeast rice, so co‑use can be considered for some people. ^[8]
• The main safety concerns come from the statin‑like effects and variability of red yeast rice itself muscle and liver risks, interactions with other drugs, and inconsistent product quality so medical supervision and careful product selection are wise. ^{[1] [3] [7] [6]}

Would you like me to review your current medication and supplement list to spot any red flags before you start red yeast rice?