We performed sympathetic skin response (SSR) studies on 29 male patients diagnosed as chronic alcoholics according to DSM-IV criteria. The average age was 43 years and the mean duration of alcohol abuse was 21 years, with all patients having a history of alcohol abuse for a minimum of 4 years. None of the patients had any symptoms and/nor signs related to autonomic nervous system dysfunction and all demonstrated normal nerve conduction velocities. Hand and foot latencies in alcoholics were prolonged relative to controls and the difference was statistically significant: reflected by p values of 0.02 and 0.004, respectively. Forty-four percent of patients demonstrated abnormal results. The unilateral prolongation of the lower extremity latency was the most commonly found abnormality (24%). Finding abnormal SSR in this patient population has made us aware that SSR has the potential to detect subclinical autonomic nervous system dysfunction even in patients who do not have autonomic complaints or neuropathy and to provide information about a part of the peripheral nervous system small unmyelinated C fibers that can not be assessed by currently performed techniques used in clinical EMG laboratories or by physical examination. © 2006 Elsevier Ltd. All rights reserved.