Background & Objectives: Dysmenorrhea is a common complaint among women, which is occasionally accompanied by gastro-intestinal problems. This study was designed to consider the therapeutical effects of vitamin E on gastro-intestinal symptoms such as nausea, vomiting and diarrhea due to primary dysmenorrhea.

 Methods: This was an experimental randomized study. A questionnaire was given to three hundred girl students suffering from primary dysmenorrhea. Then 128 girls who had gastro- intestinal symptoms accompyning dysmenorrhea entered the study. 69 subjects were assigned to case group and 59 to control group. From two days before the period until three days after it, four pills of vitamin E (400IU) daily were given to the case group and four chewing placebo were given to the control group as well, for four months. The data were analyzed by SPSS using Chi-square test.

 Results: The findings showed no significant difference between the two groups in terms of gastro-intestinal symptoms after two months of treatment. But after four months of treatment there was a significant difference in the gastro-intestinal symptoms between the two groups (p=0.001).

 Conclusions: Vitamin E is effective to be used after the second month of treatment to treat the gastro-intestinal symptoms in girls with primary dysmenorrhea.