[header] How to treat nausea and diarrhea during your period [title] Identify the source of the nausea. [step] Chronic nausea that coincides with monthly menstruation suggests that pms is the culprit. But there are other causes for nausea, some more serious than others. 
If your nausea symptoms do not go away after menstruation or become more serious, then see a doctor. Some common causes of nausea include : [substeps] Medication inducement: people with sensitive stomachs often have to take medications or vitamins with a small meal or a glass of milk to prevent nausea.