OBJECTIVE: The authors sought to examine central GABA(B) receptor responses in patients with generalised Social Anxiety Disorder using the growth hormone (GH) response to baclofen. METHOD: Baclofen 20 mg was administered to 15 patients and 15 healthy matched controls and plasma growth hormone was monitored over a 3 h period. RESULTS: The GH response in patients was significantly reduced in comparison to that of controls when calculated as both area under the curve (AUC) and delta (Delta) response. CONCLUSIONS: The results suggest an abnormality of central GABA(B) receptor function in this disorder. Copyright 2002 John Wiley & Sons, Ltd.