In this project, we explore the pathophysiology of two important clinical problems frequently observed in the chronic alcoholic during withdrawal: (1) disturbed sleep-wake cycle, and (2) increased susceptibility to infection. Twenty-four hour measurements of body temperature, motor activity, ambulatory EEG, and urinary catecholamine excretion are performed on acutely withdrawing alcoholics during withdrawal. Although originally this study was designed to obtain these measurements during the first 72 hours of withdrawal, recent research from our ward indicates that this time frame should be altered. We are, therefore, evaluating biologic rhythms in 24 hours on days one, three, and eight of withdrawal. Also, plasma cortisol is obtained every half hour and plasma ACTH and melatonin is determined every hour (rather than every three hours as originally proposed) during these periods. Because of limitation on the total volume of blood samples, lying-standing norepinephrine determinations are not be obtained. Alcoholic patients and age- and sex matched controls are evaluated for general immunocompetence to determine the effects of long-term alcohol abuse and withdrawal from alcohol on the immune system. Patients are evaluated at regular intervals to investigate effects of varying durations of abstinence from alcohol on selected parameters of immunocompetence.