The medical treatment of acromegaly

Acromegaly can be treated with several medical modalities. The growth hormone (GH) receptor antagonist pegvisomant, in particular, is able to reduce serum insulin-like growth factor I (IGF-I) concentrations to almost any desired level. Along with this important achievement come other practical issues. The most important is that IGF-I also has metabolic actions, especially the control of serum glucose concentrations. As somatostatin analogues and pegvisomant have their own intrinsic differential effects on serum GH levels and actions as well as on serum IGF-I levels and actions, it should not automatically be assumed that absolute concentrations of these parameters of disease activity reflect the same levels of action. In the ideal situation we should be able to develop treatment of specific target levels for both GH and IGF-I that might even be patient-specific as well. To date we have not moved as far as this, but awareness of treatment-specific differential effects might help us to understand some of the signs and symptoms that we encounter in acromegalic patients.