Infection is now accepted as a stressor, consequently we sought to compare the short- and longer-term consequences of several environmental stressors versus an endotoxin challenge on alcohol-induced motor ataxia. The present set of studies examined the impact of intermittent electric shock (SHOCK), intermittent cold water swim (ICWS), or lipopolysaccharide (LPS) administration on the motor ataxic effects of an intraperitoneal (i.p.) injection of alcohol (ETOH). In Experiment 1 SHOCK, but not ICWS, enhanced the motor ataxic effects of ethanol at both 2 and 24 h post-stress. In Experiment 2 administration of LPS did not affect the motor ataxic effects of ETOH 4 h later, but enhanced the ataxic potency of ETOH 24 h later. The results indicate that certain environmental and immune stressors have the potential to alter the long-term behavioral reactivity to alcohol. These examples of stress-induced enhancement of the motor ataxic effects of ETOH may have important implications for the development of alcohol dependence.