A pilot study to evaluate the effect of acute and long-term administration of cyclandelate on the vigilance of subjects submitted to hypoxic conditions. Preliminary report.

A pilot study of a double-blind crossover design was carried out in four healthy male volunteers. 3,5,5-Trimethylcyclohexyl mandelate (cyclandelate, Cyclospasmol) 800 mg b.d. was compared with placebo using two-week treatment periods separated by a wash-out-period. Under hypoxic conditions (11.5% O2) the volunteers were asked to perform a series of tests including a computer-assisted oculodynamic test (ODT) after one dosage and after fourteen days' treatment with both cyclandelate or placebo. ODT is a very sensitive test which is independent of learning or motivation. Certain cardiovascular and respiratory parameters were simultaneously recorded during the test periods. The results showed that cyclandelate protected the volunteers against the effects of hypoxia. The results after two weeks' treatment were more definite than those after the first dose, suggesting that cyclandelate acted centrally on cerebral metabolism rather than through a direct cerebrovascular effect.