Dr. Rawls is a licensed medical doctor in North Carolina and a leading expert in integrative health. He has extensive training in alternative therapies, and is the Medical Director of Vital Plan, a holistic health and herbal supplement company in Raleigh, NC.
Passionflower is a beautiful climbing vine that’s as pacifying to look at as it is to consume. Taken orally, passionflower promotes relaxation and calm and has long been used to maintain a healthy nervous system and support restful sleep.
Passionflower is a perennial herbaceous vine with trident shaped leaves, fruit about the size of a duck egg, and beautifully intricate flowers that open and close with each day. While there are over 550 species in this genus, many of which are called passionflower, only this species, Passiflora incarnata, has a strong history of use in herbal medicine traditions, and others may be toxic or at least less therapeutic. A close relative of the cultivated passion fruit (Passiflora edulis) that is commonly eaten in Central America, passionflower produces fruits with a similar taste, though less sweet.2
When Spanish missionaries first noticed passionflower, they felt that the arrangement of the flower parts symbolized the Passion of Christ, hence the Latin name. Before European contact, however, passionflower has long been an essential plant to Native Americans for both food and medicine and is also an ecologically important plant, well-loved by many pollinators.
Today the aerial plant parts (leaf, vine, and flower) are used primarily to help support a healthy and calm nervous system as well as to promote normal sleep without causing any next-day grogginess.3
Passionflower is known in herbalism as a nervine; an herb that relaxes tension and eases anxiety by soothing both the body and mind.4 Nervines, especially in combination with adaptogens, are a powerful antidote to stress.
How does passionflower do it? It works through a combination of phytochemicals working together to gently tune and support various aspects of the nervous system. Some of the phytochemicals present in passionflower that have been isolated and studied include:
Passionflower herb is also thought to boost levels of GABA, a calming neurotransmitter that inhibits specific brain signals and decreases activity in the nervous system. This can promote relaxation and help with feelings of anxiety, stress, and fear.6,7
Small human studies confirm the historical use of passionflower for generalized anxiety. It was also found to have minimal or no job impairment side effects compared to certain anxiety medications.8
In another human clinical trial, patients were given a passionflower supplement prior to surgery and had significantly lower anxiety scores heading into the procedure without losing psychomotor function.9
An agitated nervous system is one of the biggest barriers to getting good sleep, especially when the mind gets stuck ruminating on repeating, unsettling thoughts. Enter passionflower. Thanks to the nervine qualities mentioned above, passionflower promotes better quality sleep by supporting and calming the nervous system.
It also helps individuals fall asleep faster due, at least in part, to two mildly sedating phytochemicals called harmine and harmane found in passionflower at very low levels.
A double-blind, placebo-controlled human study on passionflower for sleep quality showed benefits for healthy adults, confirming its use in Western herbalism for sleep support over the past 150+ years.10
Clinical use of passionflower indicates that it may help relieve stress-induced headaches, likely due to its hypotensive and calming qualities.
Passiflora has also been used to support individuals with ADHD. One small clinical study of children with ADHD found that taking passionflower for 8 weeks was comparably as effective as taking the drug methylphenidate, aka Ritalin, but without the same negative side effects.11
While more research is merited, a human opiate detoxification study found that using passionflower as an adjunct to clonidine, the primary treatment for opioid dependence, significantly improved the management of mental symptoms throughout the 14-day process.12
Preliminary animal research indicates that there may be similar benefits for use with alcohol withdrawal.13 These findings support the use of passionflower in some traditional medicine systems for helping manage withdrawal symptoms.
Cherokee Native Americans used the root as a poultice for inflammation and minor skin ailments such as boils and scratches and they cooked and ate the young leaves.14 While passionflower was likely not a staple food source, many native groups of the Southeastern U.S. enjoyed the late summer fruit, which could be opened and eaten straight or made into juice thickened with cornmeal to create a cooling beverage.15 This practice was later adopted and modified by Westerners who made a syrup from the fruit as a cooling agent for fevers.
In 1787, surgeon Johann David Schoepf documented using the leaf as an antispasmodic for the “staggers or epilepsy” during the Revolutionary War. The herb made its way to Europe during this time, where it gained popularity, and its use as a nervine was first pioneered.
It was later repopularized in its native land by Dr. L. Phares of Mississippi, who recorded using it in 1840 as a sleep aid and mild nerve sedative. Eclectic physicians of the late 19th and early 20th century, known for using botanical remedies, continued using passionflower for insomnia, nervousness, spasmodic conditions, and mental worry, especially for overworked individuals.16
While the fruit may be cultivated or wild foraged and enjoyed as food, the most medicinal parts of the plant typically used are the vine, leaves, and flowers. Passionflower extracts such as a water-alcohol extract or dried powder extract typically yield the most potent therapeutic effects.
Passionflower tea may be made by steeping 1-2 tsp. of the dried herb in 1 cup of hot water for 20-30 minutes and taken 2-4 times per day. This grassy, earthy-tasting tea does well with the addition of a bit of honey.
If using a tincture, general dosing ranges from 3 to 4 mL up to 4 times per day.
For powdered extract capsules, look for products standardized to 3.5% vitexin. Vitexin is one of the notable phytochemical constituents in passionflower that has hypotensive properties and is often used as a marker of product potency. Depending on the product quality, concentration, and whether or not it’s being used in combination with other herbs, general dosing ranges for the extract are between 250 mg to 500 mg, 1 to 2 times daily.
For sleep support, take passionflower before bedtime and again if needed during middle-of-the-night awakenings. For this use, consider pairing passionflower with L-theanine, lemon balm, GABA supplements, melatonin, and CBD.
For anxiety, nervous system, and mood support, passionflower may be taken during the day or stressful periods, as needed. For this purpose, consider other herbs and ingredients such as ashwagandha, bacopa, reishi, lion’s mane, ginkgo, and gotu kola.
There are theoretical concerns that passionflower may potentiate the effects of prescription sedatives and anxiety medications, so caution is advised if using them together. Avoid use with older type antidepressants such as MAO inhibitors.
Always check with your healthcare practitioner before use if you are taking medications. For more general education on potential interactions between herbs and medications, check out this article by Vital Plan’s Medical Director, Bill Rawls, MD: Is it Safe to Take Herbs with My Medications?
The safety of using passionflower during pregnancy is unknown, so it’s recommended to avoid it during this time.
While passionflower is generally considered safe, it may cause drowsiness, so avoid using heavy machinery or driving until you know how strongly the herb affects you.
Want to see the science? Check out our references below.
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6. Grundmann O, Wang J, McGregor GP, Butterweck V. Anxiolytic activity of a phytochemically characterized Passiflora incarnata extract is mediated via the GABAergic system. Planta Med. 2008 Dec;74(15):1769–73.
7. Elsas S-M, Rossi DJ, Raber J, White G, Seeley C-A, Gregory WL, 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 Int J Phytother Phytopharm [Internet]. 2010 Oct [cited 2021 Jul 16];17(12):940. Available from: https://www.ncbi.nlm.nih.gov/labs/pmc/articles/PMC2941540/
8. Akhondzadeh S, Naghavi HR, Vazirian M, Shayeganpour A, Rashidi H, Khani M. Passionflower in the treatment of generalized anxiety: a pilot double-blind randomized controlled trial with oxazepam. J Clin Pharm Ther. 2001 Oct;26(5):363–7.
9. Movafegh A, Alizadeh R, Hajimohamadi F, Esfehani F, Nejatfar M. Preoperative Oral Passiflora Incarnata Reduces Anxiety in Ambulatory Surgery Patients: A Double-Blind, Placebo-Controlled Study. Anesth Analg [Internet]. 2008 Jun [cited 2021 Jul 19];106(6):1728–32. Available from: https://journals.lww.com/anesthesia-analgesia/pages/articleviewer.aspx?year=2008&issue=06000&article=00019&type=Fulltext
10. Ngan A, Conduit R. A double-blind, placebo-controlled investigation of the effects of Passiflora incarnata (passionflower) herbal tea on subjective sleep quality. Phytother Res PTR. 2011 Aug;25(8):1153–9.
11. Mohammadi M-R, Akhondzadeh S, Momeni F. Passiflora incarnata in the treatment of attention-deficit hyperactivity disorder in children and adolescents. Therapy. 2005 Jul 1;2:609–14.
12. Akhondzadeh S, Kashani L, Mobaseri M, Hosseini SH, Nikzad S, Khani M. Passionflower in the treatment of opiates withdrawal: a double-blind randomized controlled trial. J Clin Pharm Ther. 2001 Oct;26(5):369–73.
13. Schunck RVA, Macedo IC, Laste G, de Souza A, Valle MTC, Salomón JLO, et al. Standardized Passiflora incarnata L. Extract Reverts the Analgesia Induced by Alcohol Withdrawal in Rats. Phytother Res PTR. 2017 Aug;31(8):1199–208.
14. Howell P. Medicinal Plants of the Southern Appalachians. BotanoLogos Books; 2006. 262 p.
15. Blankespoor J. Passionflower’s Medicinal & Edible Uses | Chestnut School [Internet]. Chestnut School of Herbal Medicine. 2012 [cited 2021 Jul 8]. Available from: https://chestnutherbs.com/passionflower-ecology-cultivation-botany-and-medicinal-and-edible-uses/
16. Foster S. Passiflora incarnata – Steven Foster’s Herbalblog [Internet]. [cited 2021 Jul 9]. Available from: https://www.stevenfoster.com/herbalblog/?tag=passiflora-incarnata