CoQ10. Coenzyme Q10 was discovered by Crane et al. (6) in 1957. Coenzyme Q10 is a naturally occurring, fat-soluble quinone that is localized in hydrophobic portions of cellular membranes. Approximately half of the body’s CoQ10 is obtained through dietary fat ingestion, whereas the remain- der results from endogenous synthesis (7). Coenzyme Q10 participates in electron transport during oxidative phos- phorylation in mitochondria, protects against oxidative stress produced by free radicals (8), and regenerates active forms of the antioxidants ascorbic acid and tocopherol (vitamin E) (9,10). Statins block production of farnesyl pyrophosphate, an intermediate in the production of CoQ10 (Fig. 1). This fact plus the role of CoQ10 in mitochondrial energy production and the importance of mitochondria in muscle function has prompted the hypoth- esis that statin-induced CoQ10 deficiency participates in statin-associated myopathy.