Syrian Rue (Peganum harmala) is native to the Mediterranean to northern India, Mongolia, and Manchuria. It's fruit are used as a red dye, and the seeds as a spice. Grows best in dry - subtropical regions.
The seeds possess hallucinogenic alkaloids harmine and harmaline. It was often employed in Asia in religion to induce halucinations. Can induce a sense of euphoria and a lowering of inhibitions, and is known to cause vomiting and halucinations if taken in excess. Excessive use depresses the central nervous system, although small quantities are claimed to be 'theraputic'. Also used historically as a "truth drug".
The seed has also been used as an anthelmintic in order to rid the body of tapeworms.