To minimize the rate of side-effects, a retrospective analysis of 28 s
tudies of GH replacement therapy in adults indicates that the maintena
nce dose should usually not exceed 1.0 IU/m(2)/day (about 1.5-2.0 IU/d
ay) in GHD patients 40-60 years old, or 1.5 IU/m(2)/day (about 2.5-3.0
IU/day) in GHD patients 20-40 years old. GHD women may tolerate, and
in fact may need, higher replacement doses, though this issue requires
further investigation. GH treatment should be started at a low dose,
i.e. about 1.0 IU/day, and increased gradually, by about 0.5 IU per mo
nth, until the target dose is reached. In the absence of side-effects,
the GH dose may be either too low, adequate, or too high. Measurement
of GH-dependent serum markers provides the most promising approach to
detect both GH depletion and excess, with serum IGF-I concentration t
he current method of choice. Clinical awareness of symptoms of GH exce
ss remains important, however, particularly in patients with IGF-I lev
els in the high normal range.