"Pregnant, Breastfeeding Women and Children: Rue contains emmenagogue effects, thus an ingredient to trigger menstruation. It also contains abortifacient effects, which can cause miscarriage if used by pregnant women. Use rue with caution because it can cause death. Children should not use rue in any way or form.

Kidney and Liver Problems: Individuals suffering from urinary tract problems, kidney or liver problems should not use rue as food or medicine. Rue can irritate these body parts making your problems worse.

Stomach and Intestinal Problems: Avoid rue if you have inflammatory bowel disease or colitis, or ulcers." -Source