Passion flower refers to vines in the genus Passiflora—flowering plants known for their showy flowers. The plants were named for the passion of Christ, because the flower structure seemed symbolic of Jesus' scourging, crowning with thorns, and crucifixion. Passion flowers are native to tropical and sub-tropical America. However, a number of species of Passiflora are cultivated outside their natural range (where some have become established) because of their beautiful flowers.

GoldBamboo

... Oral passion flower products are most frequently used for their effects on the central nervous system. While not all of these effects are understood, it is known that certain chemicals in passion flower may act like a prescription drug class known as benzodiazepines. Drugs like benzodiazepines and herbals such as passion flower increase levels of a neurotransmitter known as gamma-aminobutyric acid (GABA). Neurotransmitters are chemicals that carry messages from nerve cells to other cells. In general, GABA decreases the activity of nerve cells in the brain, causing relaxation. This effect may make passion flower helpful in treating anxiety. Passion flower also may be used to treat insomnia. In addition, it contains chemicals known as harmala alkaloids, which are thought to block an enzyme involved in depression. This enzyme, monoamine oxidase, breaks down other neurotransmitters -- especially dopamine, norepinephrine, and serotonin -- which are involved in mood stability. Blocking monoamine oxidase may increase the amounts of these additional neurotransmitters and may improve mood. No large human studies have been performed to prove the effectiveness of passion flower for these uses, however. ...
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?Maypop Passiflora incarnata flower and bee Scientific classificatio ...
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