The dopamine agonist, pyridoxine, was administered to 10 children being evaluated for short stature. Serum GH and PRL responses were contrasted to those after insulin-induced hypoglycemia (ITT) and L-dopa administration. Levels of GH did not change after pyridoxine, but PRL fell (P less than 0.05) to 42% of the zero time concentration. Significant increments of GH occurred during ITT and after L-dopa, while PRL was suppressed to a greater extent by L-dopa. We conclude that pyridoxine is not useful in assessment of hypothalamic-pituitary function.