Passiflora incarnata is a climbing plant native of tropical America, with characteristic flowers and fruits, the latter giving a delicious juice. Passion flower was widely used by the Aztecs to induce perspiration, as a sedative, and as an analgesic. Its main active ingredients include glycosides, flavonoids, harmol, harman, harmalol, maltol, passicol, and the alkaloids aribine, harmine, harmaline, loturine, passiflorine, yageine and others. Harmine, harmaline and other alkaloids are monoamine oxidase inhibitors and would be naturally synergistic with tryptophan. Harmine was used by the Germans during World War II as a truth serum.
- Analgesic. Passion flower extracts provide a measure of pain reduction, something that is common with other herbs that combine anti-spasmodic and nerve-calming properties.
- Anti-spasmodic. The anti-spasmodic effect of some passion flower alkaloids on the central nervous system, appears to include a spasm-resolving effect on smooth muscle tissue, and at the same time a reduction in locomotor activity.
- Nerve relaxant. Low levels of the neurotransmitter serotonin have been identified in passion flower extract, perhaps involving a rather complex action on the brain and central nervous system. This may help explain the use of this herb as a natural sedative and calmative, a mood shifter from irritability, anxiety and nervous tension to relaxation, and a general aid to concentration.
- Sedative. Another compound, maltol, has been shown to have mild sedative properties. The traditional use of passion flower as a natural sedative is now backed up by research showing a beneficial effect on sleep patterns, such as the quality and duration of sleep. Unlike sedative drugs, however, passion flower can treat insomnia without dependence or side effects such as confusion, depression and stupor.
- Vasodilator. The same alkaloids mentioned above as anti-spasmodic, have the additional effect of lowering the blood pressure and dilating the coronary arteries of the heart.
Caution. It must not be used during pregnancy.