General Description
Passionflower (also known as maypop or apricot vine) is a perennial,
woody, climbing vine native to the southeastern United States. Reaching
up to roughly ten meters in length, passion flower has gray, striated
bark and alternate, palmate leaves with three to five finely toothed
lobes. The plant flowers from early to late summer, producing rayed
blossoms with a diameter of 5 to 9 centimeters. The flowers consist
of five sepals, which are white on the inside and green on the outside,
and five petals, which are white to pale red. At the center of the
flower is a secondary corona consisting of four rings of purple,
threadlike structures. The fruit (or granadilla) is a smooth, yellow-orange,
ovate berry, about 7 or 8 centimeters long, with sweet, edible pulp
and numerous seeds. The above-ground portions of the plant are used
for medicinal purposes.
Health Applications
History and Traditional Use
Although medical use of passionflower did not begin until the
mid 19th century, the plant has a history of religious symbolism
that begins more than two hundred years earlier, when Jesuit missionaries
viewed the plant's attributes as representative of various elements
surrounding the crucifixion (or passion) of Christ and, thus,
named it passionflower. While passionflower's religious significance
would fade over time, the plant would eventually become the center
of political controversy. In 1919, the General Assembly of Tennessee
designated that a state flower be chosen by the school children
of the state, and passionflower was selected. This designation
was called into question in 1933 when the state legislature selected
the iris as the "State Flower of Tennessee" without formally recinding
the previous selection of passionflower. To rectify the confusing
situation, in 1973 passionflower was named the state wildflower
and the iris the state cultivated flower. Passionflower was introduced
into medicine in 1840 by Dr. L. Phares of Mississippi, but remained
largely obscure until it was reintroduced by eclectic physicians
later that century.1 For many years following,
the herb was used as a calmative and sedative herb, and it was
listed in The National Formulary from 1916 to 1936.1
Although passionflower has since fallen out of use in the U.S.,
it remains popular as a medicinal herb in Germany and other European
countries.
Chemical Composition
The constituents responsible for passionflower's activity in the
body are still the subject of debate. It is possible that the
herb's effects stem from the interaction of multiple principles.
Compounds found in passionflower include coumarin derivatives,
maltol, and small amounts of essential oil and alkaloids.2
The plant also contains numerous flavonoids, including vitexin,
isoorientin, schaftoside, isoshaftoside, and chrysin, which may
contribute to its biological activity.1,3
Contemporary Uses
Modern medicinal uses of passionflower focus primarily on its
anxiety-reducing and sedative properties, much in keeping with
traditional applications. Germany's Commission E lists passionflower
as an approved herb for treatment of "nervous restlessness," and
animal studies indicate that various compounds in the herb may
have sedative and antianxiety effects.3-5
Studies examining the effects of passionflower on human subjects
are lacking.
Dosage/Toxicity
The daily dosage approved by Commission E is 4 to 8 grams of the
herb or equivalent preparations.2 To make
an infusion, 150 milliliters of water can be poured over one teaspoon
of the herb and strained after ten minutes. There are no known
health hazards or side effects at this dosage range.6
Passionflower toxicity has been reported in the case of a 34-year-old
Australian female who experienced such symptoms as nausea, vomiting,
drowsiness, and accelerated heart rate;7 however,
the amount, purity, and potency of the formulation used in this
case have not been determined. |
