Mean (± S.E.M.) responses per session on the EtOH lever by P rats given saline (n = 4–5/time point), or 0.1, 0.3, or 1.0 mg/kg nicotine (n = 7–9/group/time point) immediately or 4-hr prior to only the first relapse session. Upper Panel: asterisk (*) indicates that rats administered 0.1, 0.3, or 1.0 mg/kg nicotine immediately prior to the first relapse session responded significantly (p < 0.05) less than baseline, and rats given saline had higher responding than baseline. Pound symbol (#) indicates that all doses of nicotine reduced EtOH responding during the first relapse session compared to the saline group (p<0.05). Lower Panel: asterisk (*) indicates that rats administered saline or 0.1, 0.3, or 1.0 mg/kg nicotine 4-hr prior to the first relapse session responded significantly (p < 0.05) more on the EtOH lever compared to baseline levels. Pound symbol (#) indicates that 0.3 and 1.0 mg/kg nicotine increased EtOH responding significantly more than the saline group (p < 0.05).