Passion Flower

• Properties and Uses
• Toxicity Levels

DESCRIPTION

Common names:

Habitat: grows in partially shaded dry areas, and along fences and woods of the United States.

Description: It has a long vine which grows for 30 feet in length and bears alternate, serrate leaves with finely toothed lobes. The flowers are white with purple centers developing in the leaf axils, blooming from May to July. The fruit is a smooth, yellow, ovate berry containing numerous seeds.

Medicinal parts:

Plant - dried, collected after some of the berries have natured

Flower - dried

CHEMICAL COMPOSITION

* For definition of some of the above terms see the dictionary section of this book.

FOLKLORE

Passion flower has a mild sedative effect that encourages sleep. This property has been well-substantiated in numerous studies on animals and humans. Nervous symptoms and cramps that inhibit sleep are alleviated by ingestion of the herb, and leading quickly to restful uninterrupted and deep sleep. When Spanish explorers first encountered the Indians of Peru and Brazil, they found this plant used in native folk medicine as a sedative. They took it back to Spain, from whence it gradually spread throughout Europe. It was in Europe that the leaves of the plant first found use as a sedative and sleep-inducing substance. Interestingly, its sedative effect was not noted by American until lately.

Today, more than 400 species of passion flower are found throughout the world. The active constituents of passion flower can be broadly classified as alkaloids and flavonoids, supported in their actions by a variety of other constituents, including amino acids, sugars, coumarins, and alcohols (actually sterols).

A decoction of passion flower has been successfully used in bronchial asthma. It has been used in Europe and America as a topical treatment for burns; compresses of the herb have a marked effect on inflammations.

The leaves of Passiflora edulis are used in South America as a diuretic and for hemorrhoidal inflammations. In Brazil, Passiflora incarnata is used as an antispasmodic and sedative. In North America, passion flower is often used as an analgesic and anticonvulsant, with some success noticed in cases of tetanus. In Italy, a combination of passion flower, belladonna, and lobelia is used to treat asthma. In Poland, a proprietary drug for treating excitability, contains an extract of passion flower.

Numerous homeopathic drugs contain passion flower; it is possible that the main sedative activity of the plant is truly homeopathic in nature, being in that respect a function of the harman alkaloid constituents otherwise stimulant in nature.

Passion flower has been commonly used in the treatment of nervous, high-strung, easily excited children; cardiovascular neuroses; bronchial asthma; coronary illness; circulation weakness; insomnia; problems experienced during menopause; concentration problems in school children; and in geriatrics. There is some experimental support for these applications.

Passion flower appears completely nontoxic, and has been approved for food use by the FDA.

Properties and Uses

Passion flower has related analgesic, sedative, sleep-inducing, and spasmolytic effects.

The major pharmacological effect of passion flower, first observed nearly a hundred years ago and consistently reported ever since, is a sedative property. The analgesic property of this herb was also observed, and doctors had success treating the sleeplessness experienced by neurasthenic and hysteric patients, as well as that caused by nervous exhaustion. Early investigators noticed that the herb worked best when sleeplessness could be traced to an inflammation of the brain; passion flower appeared to act as an analgesic and was free from side effects. Later in this century, investigators discovered that the flavonoid fraction was more effective. However, other tests showed that the most effective sedative activity was obtained from a combination of both the flavonoids and the alkaloids.

Early research indicated that an extract of passion flower was effective against the disturbance of menopause, and as agent against the sleeplessness that occurred during convalescence from the flu. The herb had no side effects, and appeared to induce a normal peaceful sleep. Observations on the day following administration revealed no depression of body or mind, in contrast to the morning-after effects usually experienced with narcotic drugs.

Passion flower is one of the main constituents of a German sleeping pill called Vita-Dor. This product, also containing aprobarbital, valerian root, hops, mellissa, and thiamine, is highly effective in inducing and maintaining sleep throughout the night. A recent Romanian patent was issued for a sedative chewing gum that contains passion flower extract in a base of several vitamins. Many other examples of the widespread application of passion flower in Europe could be cited; however, American recognition of the sedative effects of passion flower has lagged seriously behind.

Some of passion flower's main constituents are the harmine and harman alkaloids (passiflorine, aribine, loturine, yageine, etc.). In man small doses (about 3-6 mg) stimulate the central nervous system, much like coffee and tea (black). In larger doses (15-35 mg), these alkaloids produce a strong motoric restlessness followed by drowsiness. Still larger doses intensify the motoric activity and cause hallucinations, convulsions, and vomiting. Oral doses of 300-400 mg will produce marked psychotic symptoms, replete with hallucinations, followed by pronounced central nervous system depression. Hence, passion flower is sometimes used as a mild hallucinogen. Since large doses of pure harman alkaloids are needed to produce psychoactive symptoms of any merit, use of the whole plant probably has no such observable effect.

Pharmacological investigations in animals indicate that relatively large doses of harman derivatives excite the central nervous system, producing hallucinations and convulsions that appear to be of extrapyramidal origin. These effects do not agree with the properties of the whole plant. Harman alkaloids arrest spasms in smooth muscle, lower the blood pressure, and expand the coronary vessels, effects which have also been observed in whole herb extracts and appear occasionally in the folk literature. A centrally-depressive chemical, a gamma-pyrone derivative called maltol, has been isolated from passion flower and shown to have mild sedative properties in mice; maltol could offset the stimulant properties of harman alkaloids, but it is unlikely that it account for all sedative effects observed in humans.

Presently, the active principle in passion flower remains unknown. It has been verified that the herb's alkaloid fraction is sedative, the flavonoid fraction (also containing some harman) is active, and a combination of the two is most active.

DRUG INTERACTIONS

Possible Interactions

Passion flower should be used with caution in conjunction with CNS-depressants or stimulants.

Specifically, this herb should not be used at all in conjunction with the potent CNS-depressant analgesic, methotrimeprazine.

Comments

To minimize central nervous system depression and possible synergism, it would be wise to avoid using passion flower with procarbazine antineoplastic drugs.

The neuromuscular relaxing action of passion flower may be enhanced by the use of certain aminoglycoside antibiotics, such as clindamycin.

In the absence of other hard data, it may be assumed that observable interactions occur between the many central nervous system drugs and the psychoactive principles in this herb.

Toxicity Levels

No toxicity of passion flower has been noted, although harman alkaloids have demonstrated toxic effects (as discussed in the Method of Action section).