The plant known as Ruda, or Rue (Ruta graveolens), is a perennial shrub with a long history in human culture and medicine. Native to Southern Europe and the Mediterranean region, it is recognizable by its distinctive, pungent aroma and blue-green foliage. Ancient civilizations, including the Romans and Greeks, valued and utilized it frequently. Due to the potent nature of its chemical compounds, the herb has served historically in both medicinal preparations and various cultural rituals. This article examines the plant’s traditional applications and contemporary scientific findings regarding its potential effects.
Traditional Medicinal and Folk Uses
For centuries, Ruta graveolens has been a common feature in traditional medicine systems across Europe, Asia, and the Americas. Historically, the herb was employed as a digestive aid for stomach complaints and to calm smooth muscle spasms (antispasmodic). Practitioners also administered the plant to treat nerve pain, such as rheumatism and sciatica, often applying it externally.
A significant traditional application involved its use as an emmenagogue, stimulating or increasing menstrual flow. This property was historically linked to its use as an abortifacient, a function mentioned in ancient Greek and Roman medicine. These usages highlight the plant’s powerful effects on the female reproductive system, which now serves as a major cautionary point.
Beyond physical ailments, Rue held a strong place in folklore and spiritual practices. It was commonly referred to as the “Herb of Grace” in medieval Europe and was traditionally used in rituals for purification and protection. People often hung bundles of Rue in their homes to ward off perceived negative influences or protect against pests.
Key Active Compounds and Modern Research
The biological activity of Ruta graveolens stems from a complex profile of phytochemicals, including flavonoids, alkaloids, and volatile oils. Rutin, a bioflavonoid initially isolated from the plant, is known for its antioxidant properties. The essential oil, responsible for Rue’s strong scent, is unusually rich in aliphatic ketones, primarily 2-Undecanone and 2-Nonanone.
Modern scientific inquiry has focused on validating traditional claims through laboratory and animal studies. Research suggests that Rue extracts possess potential antimicrobial properties against certain bacteria and fungi strains. Preliminary studies have also observed the plant’s anti-inflammatory effects, which may relate to its traditional use in treating conditions like rheumatism.
Other investigations include the plant’s potential cytotoxic activity. Compounds like furanoacridones and acridone alkaloids have demonstrated anti-cancer properties against human cell lines in vitro. However, this research remains preliminary, based on test-tube or animal models, and lacks conclusive human clinical trials. These findings illustrate scientific potential but do not equate to proven medical efficacy in humans.
Essential Safety Precautions and Adverse Effects
The potency that drove Rue’s traditional use also makes it a plant with considerable risks; internal consumption is generally not recommended. Ingesting the plant, especially concentrated oil or large doses, can lead to severe gastrointestinal distress, including violent vomiting and abdominal pain. Case reports have also linked internal consumption to systemic complications, such as damage to the liver and kidneys, and multiorgan toxicity.
A major external hazard associated with handling Rue is phototoxicity, caused by its high concentration of Furocoumarins, such as psoralen. Contact with the plant’s sap or leaves followed by exposure to ultraviolet A (UVA) light triggers a severe reaction known as phytophotodermatitis. This reaction is a chemical burn, not an allergy, resulting in painful, blistering lesions and long-lasting hyperpigmentation of the skin.
Individuals who handle the plant should take precautions, such as wearing gloves and avoiding sun exposure on contact areas. Furthermore, the use of Ruta graveolens is strictly contraindicated for pregnant and breastfeeding individuals. Its historical capacity to act as an abortifacient means it poses a significant risk of inducing uterine contractions or causing fetal harm. Given these serious adverse effects and the lack of established safe dosages, Rue should only be used with extreme caution.