The purpose of this study was to determine whether alcoholics with a co-existing anxiety disorder (dual-diagnosed group) experienced different withdrawal symptomatology from alcoholics without an anxiety disorder (alcohol-only group). Symptoms of alcohol withdrawal were measured on admission to an in-patient treatment program and throughout treatment (days 0, 2, 7, 14 and 21) using the revised Clinical Institute Withdrawal Assessment for Alcohol (CIWA-Ar) scale. The dual-diagnosed group exhibited more severe alcohol withdrawal, as indicated by higher total CIWA-Ar scores, at all time points than the alcohol-only group. The possibility that anxiety disorders and alcohol withdrawal share a common neurochemical basis and that the CIWA-Ar scale may be useful as a screening instrument for anxiety disorders in alcoholics is discussed.