The present study was performed to evaluate convulsions after food intake in fasted rats pretreated with scopolamine or atropine and to determine whether these convulsions respond to drugs found effective in fasted mice. Scopolamine (2.4 mg/kg) and atropine (2.4 mg/kg) were given intraperitoneally (i.p.) to rats fasted for 52 h. Both drugs induced convulsions after animals were allowed to eat ad lib. Another group of fasted rats pretreated with saline, MK-801 (0.1 mg/kg), clonidine (0.1 mg/kg), chlorpromazine (2 and 4 mg/kg), valproate (200 mg/kg), diazepam (1.5 and 2 mg/kg) or gabapentin (50 mg/kg) were treated i.p. with saline or scopolamine (2.4 mg/kg) and were allowed to eat ad lib. Clonidine, MK-801, chlorpromazine (4 mg/kg) and diazepam (2 mg/kg) reduced the incidence of scopolamine-induced convulsions in fasted rats. Gabapentin could only prolong the onset of convulsions. Neither treatment was effective against myoclonus of hindlimbs. Present results showed that fasted rats also develop antimuscarinic-induced convulsions which do not completely respond to treatments found effective in convulsions of fasted mice. (c) 2006 Elsevier B.V. All rights reserved.