Guide
How to choose a good passionflower
Choosing a passionflower product starts with the species and form, since Passiflora incarnata is what's actually been studied, then checking the label, dose, fillers, price per serving and testing.
Choosing a passionflower product starts with knowing which species and form you're buying — Passiflora incarnata is the species behind virtually all the research, and dried herb, extract and tincture aren't the same amount of anything. A few checks on the label tell you more than a marketing claim will.
Which species
Look for the species name, not just "passionflower." Passiflora incarnata is what both human trials and the European Medicines Agency's herbal monograph used and cover — a product that doesn't name a species, or names a different one such as Passiflora caerulea, isn't backed by that same research even if the label says "passionflower."
Which form
Passionflower is sold as dried cut herb (for tea), as a liquid extract or tincture, and as a powdered extract in capsules. These aren't interchangeable strengths of the same thing — a liquid extract's concentration depends on its extraction ratio (the EMA's monograph lists several, from about 1:1 to 1:8), so "1 ml" of one product isn't necessarily the same amount of herb as "1 ml" of another. See how much passionflower should you take a day? for what each form has actually been tested at.
What the label actually states
A useful label states the species, the plant part (the aerial parts — leaves, stems and flowers — is standard), the form, and, for an extract, the ratio or standardization. A label that just says "passionflower" with none of that is giving you less to go on than it could.
Dose against what's actually been tested
The two human trials used a 500 mg single extract dose for one purpose, and a nightly cup of tea for another — neither is a general daily target. Commercial capsules commonly range from around 200 mg to 800 mg of extract per serving, which is a manufacturer's serving size rather than a figure tied to either trial. Compare a label's amount to how much passionflower should you take a day? rather than assuming a bigger number is automatically better.
Fillers and other ingredients
Check the "other ingredients" line for what's added beyond the herb itself — a capsule shell, a flow agent, or, in a tea blend, other herbs like chamomile or lemon balm. None of these are inherently a problem, but a blend changes what you're actually evaluating; a product with several sedating herbs together isn't the same thing as passionflower alone.
Price per serving
Because dried herb, extract and tincture come in very different concentrations, price per bottle tells you very little on its own. Price per serving — and what that serving actually contains — is the number that lets you compare two products fairly.
Third-party testing
A certificate of analysis (COA) confirms a specific batch was tested for identity and contaminants by an independent lab. "Third-party tested" only means something when a batch has a linked, available COA to go with the claim — no link means there's nothing to check.
Questions people ask
Where can I buy passionflower?
Passionflower is widely sold as tea, capsules, tincture and liquid extract through herbal and supplement retailers. This page doesn't recommend a specific seller — the checks above (species, form, label detail, dose context, fillers, price per serving, testing) apply no matter where you buy it.
Which passionflower product should I choose?
That depends on the form you want and what you're using it for. What it shouldn't depend on is a health claim on the packaging — the research on passionflower is limited to two small human trials, covered in passionflower benefits: what the research does and doesn't show.
Related reading: what is passionflower? A plain guide, how much passionflower should you take a day?, and passionflower side effects.
Sources
- Passiflora: a review update A 2004 review of the Passiflora genus found P. incarnata has documented central-nervous-system-depressant properties in laboratory and animal research, and identified flavonoids as its major active compounds — not a human clinical trial.
- Preoperative oral Passiflora incarnata reduces anxiety in ambulatory surgery patients: a double-blind, placebo-controlled study A 2008 placebo-controlled trial found a single 500 mg dose of Passiflora incarnata extract, given 90 minutes before surgery, produced better anxiety scores in surgical patients than placebo, without added sedation or slower recovery.
- A double-blind, placebo-controlled investigation of the effects of Passiflora incarnata (passionflower) herbal tea on subjective sleep quality A 2011 placebo-controlled crossover trial found a week of nightly passionflower tea produced better self-rated sleep quality than a week of placebo tea in healthy adults with mild sleep complaints, based on sleep diaries.
*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.