In 1985 Ogasahara observed that treatment with ubiquinone produced improvement in the cardiac conduction and the metabolism of the lactic and pyruvic acids in the Kearns-Sayre syndrome. The results of the administration of 150 mg/day of ubiquinone for 3 years in a patient diagnosed with the Kearns-Sayre syndrome is described. The patient improved notably in strength, ocular movement, visual evoked potentials and in the metabolism of lactic and pyruvic acids. Other beneficial effects reported in the literature have been improvement of ataxia and the somato-sensitive evoked potentials. No side effects have been described.