Laboratory studies 1. GH stimulation test Provocative stimuli include insulin, arginine, levodopa (I-dopa), clonidine and glucagon GH response to insulin is the most reliable test for GHD GH response( GH level <10 ng/m)after given 2 provocative stimuli diagnoses gh deficiency1. GH stimulation test • Provocative stimuli include insulin, arginine, levodopa (l-dopa), clonidine and glucagon • GH response to insulin is the most reliable test for GHD. • GH response ( GH level <10 ng/ml) after given 2 provocative stimuli diagnoses GH deficiency Laboratory Studies