NOW Foods
NOW Passionflower 350 mg
Budget pick for a straightforward passionflower herb capsule.
Herb Profile
Passionflower
Passionflower is used for mild mental stress and sleep tension; evidence is traditional/emerging rather than strong.
Last reviewed: •6 human studies cited
B ModerateUse extra caution — May reduce anxiety symptoms in some studied contexts; may be relevant to sleep when anxiety is the driver. Details
- Evidence
- Moderate Human Evidence
- Typical onset
- Varies by prep
- Safety rating
- High caution
- Best for
- Sleep, Stress, Cognitive function
- Avoid / review if
- Sedatives, SSRIs (Theoretical MAOI Overlap)
Monograph visual
Passionflower
The Hippie Scientist illustration
Verdict: PassionflowerMaybe
Best for
- Mild anxiety with restlessness
- Occasional trouble winding down at night
Not ideal for
- Severe insomnia
- Panic attacks
- A same-strength benzodiazepine substitute
- Evidence confidence
- Early–moderate — a handful of supportive small trials
- Expected onset
- 30–60 minutes
- Give it
- 1–4 weeks
Bottom line: A mild, calming herb with modest trial support for anxiety and sleep onset. Best as a gentle option or stack ingredient, not a heavyweight sedative.
Safety: Can add to the sedation of alcohol or other sleep aids; avoid in pregnancy and discuss with a clinician before combining with sedatives.
On the evidence: Small randomized trials for anxiety and sleep; effects are modest.
How strong is the evidence?Limited
Why not higher
- Trials are small and often combine passionflower with other herbs
- Preparations and doses vary
- Effects are modest
Why not lower
- A few randomized trials support mild anxiety and sleep-onset benefit
- Long traditional use and good tolerability
Practical takeaway: A gentle option for mild anxiety or trouble winding down, best as a stack ingredient rather than a stand-alone fix for significant insomnia.
Where to go next — guides & comparisons
Start here — new to this? Begin with Best herbs for anxiety
Compare before choosing
- Sleep herbs vs. melatonin — if choosing a sleep-onset aid
- Beyond ashwagandha: other anxiolytics — if anxiety is the main target
Continue reading
- If you want help sleeping → Sleep guides
- If you want help with anxiety or stress → Anxiety & stress guides
- If you want to browse more herbs → All herbs
Safety & Cautions
May reduce anxiety symptoms in some studied contexts; may be relevant to sleep when anxiety is the driver. | Do not claim proven insomnia treatment or benzodiazepine replacement.
28%
High caution — review carefully
Detailed safety fields
Pregnancy, breastfeeding, and contraindications
- - Sedatives
- - SSRIs (Theoretical MAOI Overlap)
Safety classifications
- - Interaction-Aware: Medication or interaction context is explicitly noted.
- - Stimulant-Like Profile: Stimulant-like or activating caution language is present.
Full safety note
- - May reduce anxiety symptoms in some studied contexts; may be relevant to sleep when anxiety is the driver. | Do not claim proven insomnia treatment or benzodiazepine replacement. | Position as anxiety/sedative herb with limited standardized dosing evidence.
Safety labels
- - Interaction-Aware
- - Stimulant-Like Profile
Evidence-based safety
Caution when combined
These pairings share a flagged risk mechanism. They are additive-effect cautions derived from contraindication data, not confirmed clinical interactions. Consult a clinician before combining.
High-Priority Caution
26 flagged pairingsSerotonergic activity
High-Priority Caution
26 flagged pairingsSerotonergic activity
Browse the grouped cautions below. The list scrolls inside this card when long.
Serotonergic activity
- 5-HTP
- Caffeine
- crocetin
- crocin
- Crocus Sativus
- Damiana
- DMT
- Ginkgo
- Panax Red Ginseng
- Panax White Ginseng
- Harmaline
- Harmine
- Kanna
- Mucuna
- Mucuna pruriens
- Passionflower
- Passionflower Extract (Standardized)
- Phenylalanine
- Rhodiola
- Rhodiola Extract SHR-5
- Saffron
- Saffron Extract
- St. John's Wort (Hypericum perforatum)
- Tryptophan
- Yohimbe
- Yohimbine
Moderate Caution
68 flagged pairingsSedation / CNS depression
Moderate Caution
68 flagged pairingsSedation / CNS depression
Browse the grouped cautions below. The list scrolls inside this card when long.
Sedation / CNS depression
- American Yellow Lotus
- Artemisia Absinthium
- Ashwagandha (Withania somnifera)
- Bacopa
- Black Seed
- Black Tea
- Blue Lotus
- Calamus
- Catuba
- Celastrus Paniculatus
- Chamomile
- Chinese Skullcap
- Coriandrum Sativum
- Corydalis
- Cymbopogon Citratus
- Damiana
- California Poppy
- Eucalyptus
- Gastrodia
- Glycine
- Gotu Kola (Centella asiatica)
- Hops
- Hypericum Perforatum
- Jatamansi
- Jujube
- Lavender
- Lavender
- Lavender Extract
- Lemon balm
- Lemon Balm Extract
- Lemon Verbena
- Lemongrass
- Lobelia Inflata
- Longan
- Magnolia
- Melatonin
- Lemon Balm
- Milk Oats
- Mugwort
- Muira Puama
- Myristica Fragrans
- Nicotiana Glauca
- Nicotiana Tabacum
- Oatstraw
- Ocimum Basilicum
- Parsley
- Passionflower
- Passionflower Extract
- Passionflower Extract (Standardized)
- Kava
- Polygala
- Poria
- Raspberry Leaf
- Sage
- Schisandra Berry
- Schisandra Chinensis
- Scutellaria Baicalensis
- Skullcap
- Shankhpushpi
- Sophora Flavescens
- theanine
- Valeriana officinalis
- Valerian Extract (Standardized)
- Valerian Root Extract
- Valerian
- Verbena Officinalis
- Ashwagandha
- Wormwood
Evidence Summary
Evidence lens
Useful signal, but study design, dose, and population still matter.
ModerateModerate Human Evidence
Human clinical evidence: Present in source signals
Mechanistic / preclinical: Mechanism mapped — Neurotransmitter Modulation · Stress Response Modulation
Research maturity: More interpretable — Long Term Human Evidence May Be Limited.
Safety boundary: Safety note available — May reduce anxiety symptoms in some studied contexts; may be relevant to sleep when anxiety is the driver.
This profile cites 6 human studies.
How evidence grades work
Each grade reflects the strength and consistency of published human evidence — not marketing claims. Grades are based on study count, design quality, effect size, consistency, and recency.
A
Strong
Multiple RCTs, consistent direction, adequate effect size
B
Moderate
Some RCTs or consistent observational data in humans
C
Preliminary / Mixed
Animal or in-vitro only, or conflicting human data
D
Traditional / Theoretical
Traditional use only; no controlled human trials
Clinical Study Summaries (5)Cited studies informing this profile. RCTs and reviews shown first.
| Study | Type | Sample | Source |
|---|---|---|---|
Passiflora incarnata in Neuropsychiatric Disorders—A Systematic Review K. Janda; Karolina Wojtkowska; K. Jakubczyk; Justyna Antoniewicz; K. Skonieczna-Żydecka (2020) | Systematic review | — | Source → |
Passiflora incarnata in Neuropsychiatric Disorders-A Systematic Review Janda K et al. (2020) | — | — | PubMed → |
Yeung KS et al. (2018) | — | — | PubMed → |
Medicinal herbs for the treatment of anxiety: A systematic review and network meta-analysis Zhang W et al. (2022) | — | — | PubMed → |
PubMed | — | — | PubMed → |
Dosing & Timing
Dose guidance
Dose varies by preparation and trial; do not infer a universal dose without trial specific extraction. | Passiflora incarnata preparations; tea/extract/drop/combinations need separate handling.
How Passionflower Works
Simplified mechanism pathway based on preclinical and pharmacological evidence. Does not confirm clinical efficacy.
Mechanism Pathway — How Passionflower Works
CompoundTarget / ReceptorMechanismEffect / Outcome
Mechanisms & Biological Pathways
Preclinical pathways
Proposed mechanisms from in vitro and animal research; these do not confirm clinical outcomes in humans.
Neurotransmitter ModulationStress Response Modulation
Goal guides
Condition guides
Compare & Sourcing
Compare side-by-side tradeoffs or verify active marker guidelines.
Review available sources for Passionflower
Independent database mapping — evaluated separately from safety and efficacy scores.
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Affiliate-ready sourcing
Passionflower product picks
Affiliate recommendations for Passionflower. Review safety, dose, and product quality before buying.
Affiliate disclosure: we may earn a commission from qualifying links at no extra cost to you. How we stay independent.
Product Form & Quality Guidelines
When sourcing Passionflower, verify the label for:
- Standardized Extract: Confirm active content percentages on the supplement facts panel (e.g. standardized to specific marker compounds) rather than simple raw herb weights.
- Third-Party Testing: Look for independent purity labels (USP, NSF, ConsumerLab, or Eurofins) to ensure the product is free from heavy metals, solvents, and contaminants.
- Form Bioavailability: Ensure the form matches evidence-supported configurations (e.g. standardized active extracts like bacosides, withanolides, or curcuminoids) for optimal onset and digestion tolerance.
Supplement stacking
Stack Passionflower With
Commonly paired with Passionflower. Review interactions and dosage before combining.
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Safety first · Harm reduction
This information is educational and not medical advice. Start low, avoid risky combinations, and consult a licensed clinician before making health decisions—especially if you use medications, have diagnosed conditions, or are pregnant/breastfeeding.
Learn how we evaluate confidence, safety, and intensity on the methodology page.
Editorial Review
Checked against primary sources, cited evidence, and contraindication language before publication. Evidence claims, safety language, and affiliate modules are reviewed independently. Not personal medical advice.
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Botanical profile context
How to interpret Passionflower
Passionflower dosage ranges, effects, drug interactions, and harm-reduction safety guide for sleep. Moderate Human Evidence research evidence. Use this herb profile as a starting point for evidence review, not as a recommendation to start a new supplement. Botanical products can vary by plant part, extract ratio, standardization, dose, and contaminant testing, so two labels with the same common name may not behave the same way.
When reviewing Passionflower, compare the traditional-use context against the human evidence, mechanism notes, and safety cautions. Pay special attention to pregnancy, breastfeeding, liver or kidney disease, blood-pressure effects, sedation, stimulation, anticoagulant use, antidepressants, and any prescription medication overlap.
For product decisions, prefer transparent labels, named extracts, clear serving sizes, and third-party quality testing. Avoid treating a long list of possible mechanisms as proof that an herb will solve a specific condition.