
Growth hormone (GH) is secreted in a pulsatile manner and is cleared rapidly, resulting in dramatic fluctuations in GH levels.1-3 For this reason, random GH levels are generally not useful in establishing GH deficiency. A number of physiologic and pharmacologic stimuli can be used to provoke GH release. Several growth hormone stimulation protocols are described below. These tests are best performed in the morning after an overnight fast.3 Patients should be confirmed as euthyroid before these protocols are initiated.