Syrian Rue
Scientific Name(s): Peganum harmala L.
Common Name(s): African rue, Harmal shrub, Harmel, isband, Ozallalk, Steppenraute, Syrian rue, Wild rue
Medically reviewed by Drugs.com. Last updated on Jul 5, 2021.
Clinical Overview
Use
In several countries the plant has been traditionally used as an hallucinogen in ceremonies, and has found its way into modern day recreational use. Although in vitro and animal experiments suggest a role as an antimicrobial, vasorelaxant, antidepressant, analgesic, or cytotoxic agent, clinical studies are lacking to support any therapeutic application. One small clinical trial suggested analgesic benefit for knee osteoarthritis.
Dosing
Clinical applications are lacking to provide therapeutic dosages. Consumption of decoctions made from 100 to 150 g of seeds has resulted in toxic effects.
Contraindications
Harmala alkaloids (specifically harmine and harmaline) are reversible monoamine oxidase inhibitors (MAOI), thus concomitant use with MAOI medicines and tyramine-containing foods is not advised.
Pregnancy/Lactation
Documented adverse reactions. Avoid use.
Interactions
None well documented; however, constituents of P. harmala have been shown to interact with several P450 enzymes as well as monoamine oxidase (MAO), acetylcholinesterase, opioid, dopamine, gamma-amminobutyric acid (GABA), and other enzymes, and signaling pathways that are important in drug metabolism.
Adverse Reactions
Case reports of toxicity include nausea and vomiting, visual and auditory hallucinations, confusion, agitation, locomotor ataxia, tremors and convulsions, and life-threatening respiratory depression and coma. Severe gastrointestinal distress, vomiting blood, gastric ulceration, and convulsions have also been reported, as well as bradycardia and low blood pressure. Symptoms are generally of short duration (a few hours) and supportive therapy is recommended.
Toxicology
Information is limited. Elevated renal and liver function tests have been reported. Symptoms of intoxication include neurological, gastrointestinal, and cardiovascular effects.
Scientific Family
- Zygophyllaceae (Creosote-bush family)
Botany
Peganum harmala L. is native to Central Asia and the Mediterranean coasts of Europe, Africa, and the Middle East. In the 1920s, the plant was imported into the United States where it is now considered a noxious weed. The plant's bitter taste allows it to thrive as it is avoided by grazing animals.
The plant is a highly branched perennial shrub that grows from 30 to 60 cm tall. It has narrow leaves arranged alternately on fleshy, bright green stiff stems. The flowers are solitary and are small, white (or pale yellow), and 5-petaled. The fruit capsule is about 6 to 10 mm across, and is green when unripe, turning orange-brown when mature. The capsule contains small black-brown triangular seeds.1, 2, 3
History
The plant was known to Dioscorides (ca. 40 to 90 AD), Galen (ca. 129 to 217 AD), and Avicenna (ca. 980 to 1037 AD) as a psychoactive drug, and the ancient Greeks used powdered seeds to treat recurring fevers and for tapeworm. In Turkey, the dried capsules have been used as a talisman against "evil-eye," and smoke from burning the dried seeds have been used to treat mental illnesses. In Iran, Iraq, Tajikistan, Afghanistan, Pakistan, and India, the plant has been used as an hallucinogen in ceremonies, and has found its way into modern-day recreational use. It has reportedly been used as an abortifacient. In the Middle East, red dye produced from the seeds has been used for carpets.
