passion flower

Botanical name
Passiflora incarnata
Parts used and where grown
Passion flower is a climbing vine renowned for its beautiful white flowers with purple, blue, or pink calyx crown blooms. The plant is native to North, Central, and South America. While primarily tropical, some of its 400 species can grow in colder climates. The mystery of such a beautiful blossom emerging from an unassuming bud has been compared to the Passion of Christ. This inspired the plant’s name, which dates back to the 17th century. The leaves, stems, and flowers are used for medicinal purposes.
Passion flower has been used in connection with the following conditions (refer to the individual health concern for complete information):
Science Ratings - Health Concerns
** - Anxiety
* - Insomnia
* - Pain
*** - Reliable and relatively consistent scientific data showing a substantial health benefit.
** - Contradictory, insufficient, or preliminary studies suggesting a health benefit or minimal health benefit.
* - For an herb, supported by traditional use but minimal or no scientific evidence. For a supplement, little scientific support and/or minimal health benefit.
Historical or traditional use (may or may not be supported by scientific studies)
The historical use of passion flower is not dissimilar to its current use as a mild sedative. Medicinal use of the herb did not begin until the late 19th century in the United States. Passion flower was used to treat nervous restlessness and gastrointestinal spasms. In short, the effects of passion flower were believed to be primarily on the nervous system, particularly for
anxiety due to mental worry and overwork.1
The effectiveness of passion flower as a treatment for anxiety has been confirmed in a double-blind study. In that study, 45 drops per day of an extract of passion flower taken for four weeks was as effective as 30 mg per day of
oxazepam (Serax®), a medication used for anxiety.2
Active constituents
For many years, plant researchers believed that a group of harman alkaloids were the active constituents in passion flower. Recent studies, however, have pointed to the
flavonoids in passion flower as the primary constituents responsible for its relaxing and anti-anxiety effects.3 European herbal pharmacopoeias typically recommend passion flower products containing no less than 0.8% total flavonoids. The European literature involving passion flower recommends it primarily for the treatment of mild to moderate anxiety. In this context, it is often combined with valerian, lemon balm, and other herbs with sedative properties.
How much is usually taken?
The recommended intake of the dried herb is 4–8 grams per day.4 To make a tea, 0.5 to 2.5 grams of the herb can be steeped with boiling water for ten to fifteen minutes and drunk two to three times per day. Alternatively, 5–10 ml of passion flower tincture can be taken three to four times per day.

Are there any side effects or interactions?
Used in the amounts listed above, passion flower is generally safe and has not been found to adversely interact with other sedative drugs. Some practitioners suggest not using passion flower with MAO-inhibiting
antidepressant drugs because of concerns that they may interact with the harman alkaloids in passion flower.5 However, this interaction is theoretical and has not been reported in the medical literature. A single case has been reported of a 34-year-old female who developed severe nausea, vomiting, drowsiness, and heart symptoms following self-administration of passion flower. It is not known for certain if passion flower caused her symptoms.6 Passion flower has not been proven to be safe during pregnancy and breast-feeding.
At the time of writing, there were no well-known drug interactions with passion flower.