Effect of bromocriptine on serum hormones in acromegaly.

Clinical and hormonal responses to bromocriptine therapy were assessed in 10 patients with acromegaly. Although substantial falls (greater than or equal to 50%) in serum GH occurred in only 4 of the patients, subjective clinical improvement and improved glucose tolerance were seen in 9, including 2 subjects in whom serum GH rose in response to bromocriptine. Serum somatomedin levels, measured by both radioimmunoassay and radioreceptor assay, fell in only 2 subjects (both of whom had falls in GH) and did not correlate with clinical status. These results suggest that some of the reported beneficial effects of bromocriptine in acromegaly may be independent of GH secretion or somatomedin generation.