A placebo-controlled crossover trial of creatine in mitochondrial diseases

To test the efficacy and safety of creatine (Cr) monohydrate in mitochondrial diseases, 16 patients with chronic progressive external ophthalmoplegia or mitochondrial myopathy were randomized in a crossover design to receive double-blind placebo or 20 g Cr/day for 4 weeks, Cr was well tolerated, but there were no significant effects with regard to exercise performance, eye movements, or activities of daily life, The power of this pilot study was limited and future multicenter trials are needed.