Coenzyme Q10 is said to increase the efficiency of oxygen utilization and ATP production in ischemic tissue. The present study was undertaken to determine the blood levels and clinical effects of Coenzyme Q10 in 83 patients with vertigo. The mean blood level of Coenzyme Q10 in 83 patients with vertigo was 0.61±0.27 μg/ml, which was lower than the normal value of 0.81±0.34 μg/ml (p<0.01). Blood levels of Coenzyme Q10 were significantly lower in patients with sudden deafness, central dizziness and vertigo than in those with MÉNIÈRE's disease. The time course of vertigo was followed in the MÉNIÈRES's disease patients in whom blood levels of Coenzyme Q10 could be determined at various times. As a result, it was found that there was a correlation between blood levels of Coenzyme Q10 and vertigo. Briefly, the mean blood level of Coenzyme Q10 was 0.72±0.22 μg/ml during remission, while it was 0.43±0.19 μg/ml when the patients were conscious of vertigo. After 2 weeks of treatment the clinical effects of Coenzyme Q10 on vertigo were determined in a group of 14 patients on Coenzyme Q10 (Neuquinon) alone, 30-90mg/day, and in a group of 23 patients on combination therapy with Coenzyme Q10 (Neuquinon), 60-90mg/day, and an cerebral metabolic activator. The drug effect evaluations were in principle made on the basis of changes in subjective and objective symptoms at the end of treatment period. The rate of effectiveness was 90% for patients on combination therapy and 35.7% for those on single therapy with Coenzyme Q10. This result suggests that the transport of Coenzyme Q10 to tissue is enhanced when it is combined with an excitometabolic cardiovascular drug and that they pharmacologically produce a synergistic effect with each other.
