In Reply.—
We appreciate the work of Drs Meltzer et al. They suggest that the reasons for the discrepant results between our two reports lie in the smaller number of subjects and the absence of a placebo-control in our study. While the number of subjects in our study was small, an additional subject who received a dl-pindolol dose of 20 mg (not 5 mg or 10 mg) demonstrated a nearly 50% reduction in buspirone-PRL release. In addition, data from a dose-response study of dl-pindolol challenge alone in the one subject who displayed no suppression of buspirone-PRL release with the dl-pindolol dose of 20 mg, revealed a 187% peak increase over baseline in PRL release (ie, 10.6 μg/L at baseline, and 19.7 μg/L peak change from baseline) when challenged with 20 mg of dl-pindolol. Hence, it is possible for dl-pindolol to suppress a PRL response associated with buspirone