Also known as: Passiflora incarnata, Maypop, Passion vine, Vitexin
BotanicalEmerging evidence
A climbing vine used traditionally for restlessness and sleep, with a small body of human research reporting improved sleep quality without next-day grogginess.
Typical dose
250.0–800.0 mg per day
30-60 minutes before bed
What it is
Passionflower is Passiflora incarnata, a climbing vine native to the southeastern United States, used in both Native American and later European herbal practice.
The aerial parts are used, containing flavonoids including vitexin and isovitexin alongside various alkaloids. Extracts are commonly standardised to vitexin content.
There are hundreds of Passiflora species and only incarnata has meaningful research behind it, so the Latin name on the label is worth checking. It appears frequently alongside valerian, hops and lemon balm in sleep formulas.
How it works
Passionflower appears to increase GABA activity in the brain, the main calming neurotransmitter, which slows nervous system activity and promotes settling.
That is a shared mechanism with valerian and hops, which is why the three appear together so often, though the specific compounds and binding sites differ.
Unlike a sedative, it does not appear to force sleep. The reported effect is on how easily people settle and on sleep quality rather than on knocking anyone out, which fits the absence of next-day grogginess in trials.
What the evidence shows
Small controlled trials have reported improved subjective sleep quality, including one using passionflower tea over a week in healthy adults, with measurable changes in sleep recordings in some studies.
There is a body of research on feelings of unease and nervousness, including work in people awaiting medical procedures, generally reporting a calming effect without impairing alertness.
Trials are small and often short, and passionflower frequently appears in combination products, which makes isolating its contribution difficult. The consistency across small studies is encouraging without being conclusive.
Dosing
Extract doses are typically 250 to 800 mg, taken 30 to 60 minutes before bed. Tea preparations use around 2 g of dried herb infused for ten minutes.
Check for Passiflora incarnata specifically, since other species in the genus lack the research.
It tends to be gentler than valerian, which suits people who find valerian leaves them heavy in the morning. Effects on sleep quality build over a week or so of consistent use rather than appearing dramatically on the first night.
At a glance
Common forms
Passiflora incarnata extract, Standardised vitexin extract, Dried herb tea, Liquid tincture, Within sleep formulas
Half-life / duration
Acts over several hours; quality effects build over about a week
Timing
30-60 minutes before bed
Competition status
Permitted — not on the WADA Prohibited List
Category
Botanical
Safety and side effects
Passionflower is well tolerated at typical doses, with drowsiness, dizziness and confusion reported occasionally and mostly at higher intakes.
It can add to the effect of anything else that makes you drowsy, including alcohol, so combining them is worth avoiding.
Do not drive or operate machinery until you know how it affects you. Speak to your doctor before use if you take anything prescribed for mood or sleep, and stop before scheduled surgery.
Who should avoid it
Do not drive or operate machinery until you know how it affects you. Avoid combining with alcohol or anything else that causes drowsiness. Speak to your doctor before use if you take anything prescribed for mood or sleep. Stop before scheduled surgery. Avoid in pregnancy and breastfeeding.
This entry is provided for information only. Food supplements should not be used as a substitute for a varied and balanced diet and a healthy lifestyle. Consult a qualified healthcare professional before use if you are pregnant, breastfeeding, taking medication or under medical supervision.
