Possible Interaction: Arginine and Levodopa

“Significantly reduced HGH RRA/RIA ratios were seen at peak time periods following levodopa and arginine hydrochloride stimulation.”

“The data suggest that a positive response to arginine and L-dopa in combination in children, who do not respond to the usual provocative tests when administered individually, may fail to identify children with partial GH deficiency who would benefit from treatment.”

“The integrated stimulated GH response in the 31 children in whom a normal GH response to all three tests occurred suggests that the effects of L-dopa and arginine are additive.”

“The patient showed normal responses to GH provocation tests with L-dopa (peak GH concentration, 42.38 ng/ml) and insulin (peak GH concentration, 23.29 ng/ml during hypoglycemia), but a blunted response to a GH provocation test with arginine (peak GH concentration, 7.31 ng/ml).”