Twenty-seven patients suffering from sudden sensorineural hearing loss (SHL) were randomly assigned to one of two groups: a treatment group (n = 13) receiving intravenous procaine and low-molecular-weight dextran, and a placebo control group (n = 14). The effect of treatment was analyzed by means of an analysis of variance and covariance procedures. Results indicated nonsignificant differences between the groups on all outcome indices measured. Sex, age, time since the onset of symptoms to the initiation of therapy, audiogram configuration, and initial severity of hearing loss did not significantly affect the results. These findings suggest that the therapeutic effects of this vasodilator are not superior to a placebo.