The passion flower plant was first â€˜discovered’ by Spanish explorers in what is now modern day Peru in the year 1569. The plant got its name not by instilling amorous passion in these explorers; rather they believed the plant’s flowers were symbolic of Christ’s passion and his approval of their journey.  The passion flower grows wild in the southern United States and South America. In the southern U.S., it is commonly known as the maypop, wild apricot, or ocoee, which is a Native American Indian name.
Passion Flower is a well-known herb and is used widely today because of its calming effects on the nervous system. With anxiety and concordant symptoms at an all time high in modern society, passion flower is considered an appropriate remedy for relieving symptoms of tension. This herb is mainly found in combination products with other calming herbs, including hops, kava, valerian, and chamomile. In the 1970’s, passion flowers was an approved over-the-counter sedative and sleep aid, but was taken off of the market in 1978. 
The medicinal parts of the passion flower consist of those growing above ground (aerial parts), including the stems, leaves and the flowering tops. The medicinal constituents of this plant are numerous, and include flavonoids and alkaloids. 
Passion Flower Uses
The medicinal action of passion flower has been described as sedative, hypnotic, anxiolytic, and antispasmodic.  Other research has shown that passion flower can relieve pain as well.  Passion Flower exerts these effects in several different ways; some constituents bind to the benzodiazapene receptors (so-named because they were discovered as binding sites to this type of drug) in the central nervous system leading to resolution of anxiousness without memory or motor skill impairment.  Other sources reveal the ability of passion flower to decrease aggressiveness, restlessness, hypermotility (unable to stop or slow down physical movement), and to raise the pain threshold.  Other possible mechanisms of the plant’s action are detailed in the literature. 
Passion Flower has been tested in specific conditions relating to anxiety; a combination product-containing passion flower was shown to relieve symptoms in people with the diagnosis of adjustment disorder with anxious mood, while in generalized anxiety disorder, passion flower was comparable to a benzodiazapene medication for treatment efficacy in this condition. [9-10] Furthermore, when incorporated into a regimen for opiate drug withdrawal, passion flower in combination with clonidine was more effective at decreasing certain symptoms (i.e. anxiety, insomnia, agitation, irritability) of opiate withdrawal than just the drug alone. 
There are several other applications of passion flower; these include neuralgia (nerve pain), seizures, spasmodic asthma, nervousness, palpitations, high blood pressure, and pain.  Other non-nervous system related conditions for which passion flower may be of use include stomach upset, menopause symptoms, burns, and hemorrhoids (topical application). Outside of its use in the central nervous system as a calmative, passion flower appears to have some antibacterial and antifungal effects. 
Standard dosing of passion flower is Â¼ to 2 grams of crude dried herb taken three times per day, or as a tea with the same dose. The average dosing is roughly 4 to 8 grams per day. If taken in tincture form, Â½ to 2 milliliters may be taken three times a day.
Commonly reported side effects of passion flower are dizziness, ataxia (slowed movement) and confusion. Otherwise, there are a few case reports of more serious reactions (involving only one patient per report) such as altered consciousness, and severe nausea with dehydration as a result. 
General interactions (supplement, herb, food, lab):
There are no known interactions with other foods or laboratory tests. However, certain herbs or supplements that may be a problem when combined with passion flower include those with sedative properties, as their combined effects may be overwhelming. There are many herbs with sedative effects in use today. There is some small theoretical evidence that passion flower may affect platelet aggregation (blood clotting) when used with other anti-platelet herbs. Similarly, there are many herbs with this potential theoretical issue; check with a physician if taking any such herbs or supplements.
Any drugs that act as central nervous system depressants should be avoided with passion flower because of potential additive effects.  These include allergy medicines or others containing antihistamines, as well as sleep and pain medications.
Passion Flower is not known to interact negatively with any particular disease conditions.
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