Natural supplements for anxiety: Passionflower

With anxiety disorders being the most common mental illness, you are likely to encounter a patient suffering from anxiety at your practice.

If traditional medicine is not working, natural supplements such as passionflower may offer relief. Passionflower has a long history, stretching as far back as the Incan Empire, before being brought to Europe.¹ There are several varieties of the plant, including perhaps the best-known passionfruit vine (Passiflora edulis), which produces a sweet aromatic fruit that is popular in South American cooking.²

However, the P. incarnata variety is most popular for medicinal use to help with anxiety and restlessness.

Historical uses of P. incarnata

Historically, the Incans used both the fresh or dried leaves and roots of P. incarnata to make tea that was used as a sedative or to reduce pain.^1,3 The dried leaves were also smoked, similarly to cigarettes, as another way to treat anxiety or pain.¹ When the plant was brought to Europe, it was used to treat seizures, agitation, and digestive problems.⁴

The passionflower was discovered in Peru by Spanish Jesuit missionaries.^1,4 The Jesuits presented Pope Paul V with drawings and dried specimens of the plant in 1608.¹ The plant was officially given the name Passionflower, in reference to the thorn-like inner petals that resembled Christ’s crown of thorns.¹ In North America, passionflower is also known as maypops, water lemons or wild apricots.¹

How passionflower works

A 2010 study published in the journal, Phytotherapy, found that administration of P. incarnata to mice increased production of gamma aminobutyric acid (GABA), which is known to have a calming effect on brain cells.⁵

The researchers added extracts to the drinking water of laboratory mice and concluded that the calming effects of passionflower may be the result of a combination of active ingredients within P. incarnata.⁵

Another study a year later further explored the connection between P. incarnata and GABA.⁶ The researchers in this study also found a positive connection between passionflower extracts and GABA in the cortical receptors of lab rats.

Clinical trials

A 2001 study published in the Journal of Clinical Pharmacy and Therapeutics compared P. incarnata to the anti-anxiety drug oxazepam in 36 patients diagnosed with general anxiety disorder.⁷ Eighteen patients received passionflower for four weeks, while the remaining 18 received oxazepam (30 mg/day).

Although both treatments relieved symptoms of generalized anxiety disorder, those patients taking P. incarnata reported significantly less impairment with performing their job tasks, compared to those taking oxazepam.

A 2008 study in Anesthesia and Analgesia examined the use of P. incarnata to reduce anxiety among a group of 60 surgical outpatients.⁸ Thirty patients received the herb 90 minutes prior to surgery, compared to the remaining 30 patients who received placebos.

Anxiety scores for those patients receiving passionflower were significantly lower than for those receiving placebo. The authors concluded that the herb can be useful for reducing surgical outpatient anxiety without causing sedation.

More than 40 million adults⁹ (18 percent of the population) suffer from anxiety in the U.S. so there is a high chance you will have a patient with this disorder. The research seems to indicate that patients may be able to put their minds at ease by taking passionflower.

1. Katemopoulos, Maureen. “The History of the Passion Flower.” http://www.gardenguides.com/82015-history-passion-flower.html October 2010. Accessed October 2015.
2. Passiflora edulis. Accessed 10/14/2015.
3. Wikipedia. Accessed 10/14/2015.
4. The calming effects of passionflower. Accessed 10/14/2015.
5. Elsas S-M, Rossi DJ, Raber J, et al. Passiflora incarnata L. (Passionflower) extracts elicit GABA currents in hippocampal neurons in vitro, and show anxiogenic and anticonvulsant effects in vivo, varying with extraction method. Phytomedicine: International Journal of Phytotherapy and Phytopharmacology. 2010;17(12):940-949.
6. Appel K, Rose T, Fiebich B, et al. Modulation of the γ-aminobutyric acid (GABA) system by Passiflora incarnata L. Phytotherapy Research. 2011 Jun;25(6):838-843.
7. Akhondzadeh S, Naghavi HR, Vazirian M, et al. Passionflower in the treatment of generalized anxiety: A pilot double-blind randomized controlled trial with oxazepam. Journal of Clinical Pharmacy and Therapeutics. 2001 Oct;26(5):363-367.
8. Movafegh A, Alizadeh R, Hajimohamadi F, et al. Preoperative oral Passiflora incarnata reduces anxiety in ambulatory surgery patients: A double-blind, placebo-controlled study. Anesthesia and Analgesia. 2008;106:1728-1732.
9. Anxiety and depression Association of America. Facts & Statistics. ADAA.org. Published September 2014. Accessed 2/8/2016