myopathy
13 interactions related to myopathy
simvastatin + coq10
Simvastatin inhibits HMG-CoA reductase, the enzyme upstream of both cholesterol and coenzyme Q10 synthesis. This produces a measurable decline in circulating CoQ10 and may contribute to mitochondrial dysfunction underlying statin-associated muscle symptoms.
simvastatin + red yeast rice
Red yeast rice contains monacolin K, which is chemically identical to the prescription statin lovastatin. Adding it to simvastatin stacks two statins with similar mechanisms and metabolism, sharply increasing the risk of myopathy, rhabdomyolysis, and liver injury.
atorvastatin + niacin
Combining high-dose niacin (1-2 g/day, typically extended-release) with atorvastatin or other statins increases the risk of myopathy and rhabdomyolysis. The HPS2-THRIVE trial documented a fourfold excess of myopathy when extended-release niacin was added to simvastatin-based therapy, and the AIM-HIGH trial showed no cardiovascular benefit from this combination.
rosuvastatin + coq10
Rosuvastatin blocks HMG-CoA reductase, an enzyme required for both cholesterol and coenzyme Q10 synthesis. Although the CoQ10 depletion is generally smaller than with lipophilic statins, mitochondrial impairment is still one proposed mechanism for statin-associated muscle symptoms.
rosuvastatin + berberine
Rosuvastatin is taken into liver cells by the OATP1B1 transporter, and berberine has been shown to upregulate OATP1B1 in hepatocyte studies, increasing hepatic uptake of rosuvastatin. The clinical net effect (more LDL lowering vs. higher muscle/liver risk) is not well established in humans.
lovastatin + grapefruit
Grapefruit juice blocks intestinal CYP3A4, dramatically increasing lovastatin and lovastatin acid exposure. A controlled study showed lovastatin Cmax rose ~12-fold and AUC ~15-fold after high-dose grapefruit juice, sharply raising the risk of myopathy and rhabdomyolysis.
atorvastatin + coq10
Atorvastatin inhibits HMG-CoA reductase, the same upstream enzyme required to synthesize coenzyme Q10 (ubiquinone). Plasma CoQ10 levels can drop by 30-40% with atorvastatin therapy, and the resulting mitochondrial dysfunction is one proposed mechanism for statin-associated muscle symptoms.
simvastatin + berberine
Simvastatin is extensively metabolized by CYP3A4, and berberine inhibits CYP3A4 in vitro, which can raise simvastatin levels and increase the risk of myopathy and rhabdomyolysis. The interaction is bidirectional in some models (induction is also possible), making net effect unpredictable.
atorvastatin + red yeast rice
Red yeast rice naturally contains monacolin K, which is chemically identical to the prescription statin lovastatin. Combining it with atorvastatin effectively stacks two statins, sharply increasing the risk of myopathy, rhabdomyolysis, and liver injury.
seville orange + atorvastatin
Seville (bitter) orange contains the same furanocoumarins as grapefruit, including bergamottin and 6',7'-dihydroxybergamottin, which irreversibly inhibit intestinal CYP3A4. A landmark crossover study showed Seville orange juice raised felodipine AUC by 76%, comparable to grapefruit, and atorvastatin shares the same CYP3A4 metabolic pathway, raising the risk of statin-induced myopathy.
cbd + simvastatin
Simvastatin is heavily dependent on CYP3A4 for first-pass and systemic clearance, and CBD inhibits CYP3A4. Co-administration is expected to raise simvastatin and active-metabolite exposure, increasing the risk of muscle pain, transaminase elevation, and rare rhabdomyolysis.
pomelo + simvastatin
Pomelo (Citrus maxima) contains furanocoumarins that irreversibly inhibit intestinal CYP3A4, the enzyme that metabolizes simvastatin during first-pass absorption. With CYP3A4 disabled, simvastatin plasma concentrations rise substantially, increasing the risk of myopathy and rhabdomyolysis.
atorvastatin + berberine
Berberine inhibits CYP3A4 in vitro and can raise plasma levels of CYP3A4 substrates, including atorvastatin, which may increase the risk of muscle pain, liver enzyme elevation, and rhabdomyolysis. The interaction direction is complex — some animal data also show induction — but co-use is unpredictable.