Herbal Monograph
Passionflower
Passiflora incarnata L.
Passifloraceae
Gentle anxiolytic and sleep support that calms racing thoughts without morning grogginess
Overview
Plant Description
Herbaceous to semi-woody perennial climbing vine, 3-9 m long. Stems slender, herbaceous, becoming slightly woody at the base with age, glabrous to slightly pubescent, bearing axillary tendrils (coiled, unbranched) used for climbing support. Leaves alternate, palmately 3-lobed (occasionally 5-lobed), 6-15 cm wide, serrate margins, dark green above, paler and sometimes pubescent below; petioles 2-5 cm long bearing 2 stalked glands near the blade base. Stipules linear-setaceous. Flowers solitary, axillary, 5-9 cm in diameter, highly ornate and structurally complex; 5 white to pale lavender petals and 5 sepals (nearly identical in appearance); corona (the most distinctive feature) consists of multiple filamentous rays in several ranks, banded purple and white, radiating from the center; 5 stamens borne on the androgynophore (a columnar stalk elevating the reproductive parts above the corona); ovary superior on the androgynophore, with 3 styles and capitate stigmas. Fruit a fleshy, ovoid berry (the 'maypop'), 4-6 cm, green ripening to yellow, edible when ripe with sweet, aromatic pulp. Seeds numerous, flattened, embedded in pulp, enclosed in fleshy arils.
Habitat
Open fields, pastures, roadsides, fence rows, thickets, woodland edges, and disturbed areas. Prefers well-drained, sandy to loamy soils. Full sun to light shade. Tolerates poor soils and moderate drought once established. Thrives in USDA Hardiness Zones 5-9. Often found in the southeastern United States as a common roadside and pasture vine.
Distribution
Native to the southeastern United States, from Virginia and Florida west to Texas, Oklahoma, and Missouri, extending into parts of the Midwest (Illinois, Indiana, Ohio). Also native to parts of Central America and northern South America. Naturalized in many tropical and subtropical regions worldwide. Widely cultivated commercially in Italy, India, and parts of South America (particularly Brazil) for the herbal medicine market. Naturalized in parts of southern Europe.
Parts Used
Aerial parts (Passiflorae herba — leaves, stems, tendrils, and flowers)
Preferred: Dried aerial parts for infusions and standardized extracts; tincture (fresh or dried herb in ethanol-water menstruum); standardized dry extract for capsules and tablets
The aerial parts harvested during the flowering period constitute the official medicinal drug recognized by European Pharmacopoeia (Passiflorae herba), Commission E, WHO, EMA, and ESCOP. The whole above-ground herb is used, not just the flowers. The European Pharmacopoeia monograph specifies a minimum total flavonoid content of 1.5% expressed as vitexin for quality compliance. Fruit is not included in the medicinal preparation and is used only as food. NCCIH recognizes passionflower as a dietary supplement used for anxiety and sleep problems.
Key Constituents
C-Glycosyl flavonoids
C-glycosyl flavonoids are considered the primary class of active compounds responsible for passionflower's anxiolytic and sedative effects. The European Pharmacopoeia requires a minimum of 1.5% total flavonoids expressed as vitexin for quality compliance. Unlike O-glycosyl flavonoids, C-glycosyl flavonoids are resistant to hydrolysis, making them stable markers. In vitro and in vivo studies demonstrate that these flavonoids interact with GABA-A receptors and modulate GABAergic neurotransmission. Chrysin specifically binds the benzodiazepine site, though its low oral bioavailability limits its individual contribution. The overall anxiolytic effect is likely due to the combined action of multiple flavonoids rather than any single compound. Dhawan et al. (2004) provided a comprehensive phytochemical review of the Passiflora genus confirming the central role of C-glycosyl flavonoids.
Indole alkaloids (harman type)
The harman-type alkaloids in P. incarnata are present only in trace amounts and are NOT considered clinically relevant at standard doses. Early research attributed passionflower's sedative effects to these alkaloids, but modern phytochemistry has established that the alkaloid content is far too low to account for observed clinical effects. The flavonoid fraction, not the alkaloid fraction, is now understood to be primarily responsible for the anxiolytic and sedative activity. The trace alkaloid content does not produce clinically significant MAO inhibition, and routine dietary tyramine restriction is not necessary with standard passionflower preparations.
Gamma-aminobutyric acid (GABA)
The presence of GABA in passionflower adds to the plant's overall GABAergic profile, complementing the GABA-A receptor modulation by flavonoids. However, the contribution of exogenous plant-derived GABA to central nervous system effects is uncertain due to limited blood-brain barrier permeability. Peripheral GABAergic effects (e.g., on the enteric nervous system) may partly explain the antispasmodic and digestive-calming properties.
Gamma-benzopyrone derivatives
Gamma-benzopyrone derivatives represent a minor but potentially contributory constituent class. Maltol has shown sedative activity in some animal studies, though its contribution relative to the dominant flavonoid fraction is likely modest.
Essential oil
The essential oil fraction is minor in passionflower compared to aromatic herbs. Individual components like linalool have known calming properties, but the very low total volatile oil content means this fraction contributes modestly to overall effects.
Other constituents
Minor constituent classes that may contribute marginally to the overall pharmacological profile. The cyanogenic glycoside content is low in P. incarnata and not a safety concern at recommended doses.
Herbal Actions
Reduces anxiety
The best-documented and most clinically validated action of P. incarnata. Reduces anxiety and nervous tension without significant sedation at moderate doses. Akhondzadeh et al. (2001) demonstrated comparable efficacy to oxazepam (30 mg/day) for generalized anxiety disorder, with less impairment of job performance. Movafegh et al. (2008) showed significant reduction in preoperative anxiety compared to placebo. Mechanism involves modulation of GABA-A receptors by C-glycosyl flavonoids and possible enhancement of GABAergic neurotransmission. EMA well-established use for relief of mild symptoms of mental stress. Commission E approved for nervous restlessness.
[1, 3, 6, 8, 17]Supports and calms the nervous system
Acts as a relaxant nervine, calming nervous excitability and supporting healthy nervous system function. Distinguished from a pure sedative by its ability to reduce nervous tension without necessarily causing drowsiness at moderate doses. Particularly valuable for nervous exhaustion, circular or racing thoughts, and difficulty 'switching off' the mind. Classified as a nervine relaxant in the tradition of Hoffmann and other Western herbal authorities.
[1, 2, 13]Promotes sleep and deep relaxation
Promotes sleep onset and improves sleep quality. Ngan and Conduit (2011) demonstrated that passionflower tea (1 g/cup before bed for 7 days) significantly improved subjective sleep quality in healthy adults as measured by sleep diary data and polysomnography indicators. The sedative action is dose-dependent; at lower doses the anxiolytic effect predominates, while higher doses promote sleep. The sedative effect is gentle and does not typically produce morning grogginess or hangover, distinguishing it from stronger sedatives.
[2, 3, 7]Relieves smooth muscle spasm
Relaxes smooth muscle spasm, particularly in the gastrointestinal tract. The antispasmodic action contributes to its use for nervous digestive complaints, intestinal colic, and the physical tension component of anxiety. In vitro studies have demonstrated spasmolytic activity of passionflower extracts on intestinal smooth muscle. This action complements the central nervine effects for conditions where anxiety manifests as gastrointestinal spasm or tension.
[2, 13]Lowers blood pressure
Mild blood pressure-lowering effect, likely secondary to the anxiolytic and relaxant nervine actions rather than a direct cardiovascular mechanism. Passionflower may gently reduce blood pressure that is elevated due to stress or anxiety. Not a primary antihypertensive agent.
[13]Relieves pain
Mild pain-relieving properties observed in traditional use and some animal studies. Analgesic effect is likely secondary to the antispasmodic and nervine relaxant actions. Used traditionally for tension headaches and neuralgic pain. Some animal studies have demonstrated antinociceptive effects of passionflower extracts.
[13, 18]Therapeutic Indications
Nervous System
Generalized anxiety disorder and nervous restlessness
The primary indication for passionflower. Commission E positive monograph for nervous restlessness (Nervose Unruhezustande). EMA well-established use for relief of mild symptoms of mental stress. Akhondzadeh et al. (2001) RCT of 36 outpatients with GAD compared passionflower extract (45 drops/day of Passipy tincture) to oxazepam (30 mg/day) over 4 weeks; both treatments significantly reduced Hamilton Anxiety Rating Scale scores with no significant difference between groups. Passionflower-treated patients showed less impairment of job performance than the oxazepam group. Movafegh et al. (2008) RCT of 60 patients demonstrated significant anxiolytic effect (500 mg Passiflora incarnata as oral premedication) compared to placebo in preoperative anxiety.
[1, 2, 3, 6, 8]Insomnia and sleep disturbance
EMA well-established use to aid sleep. Ngan and Conduit (2011) RCT in 41 healthy adults: passionflower tea (1 g/250 mL, one cup before bed for 7 days) significantly improved subjective sleep quality compared to placebo tea (parsley), as measured by sleep diary data (Karolinska Sleep Quality Index). One polysomnographic measure (total sleep time) showed a trend toward improvement. Passionflower is considered a gentler sleep aid than valerian, particularly suitable for individuals whose insomnia stems from an overactive mind or anxiety-driven inability to relax into sleep. Does not typically produce morning grogginess.
[2, 3, 7, 13]Adjustment disorder with anxious mood and situational anxiety
Passionflower is well-suited for acute situational anxiety, including preoperative anxiety (Movafegh et al. 2008; Aslanargun et al. 2012 for spinal anesthesia anxiety), dental anxiety (Dantas et al. 2017; Kaviani et al. 2013 for periodontal treatment anxiety), and adjustment-related anxiety. The relatively rapid onset of anxiolytic effect (within 30-90 minutes for acute dosing) supports its use for situational stress, in addition to regular dosing for chronic anxiety. Sarris et al. (2013) systematic review of plant-based medicines for anxiety confirmed passionflower among the most promising herbal anxiolytics.
[8, 10, 11, 12, 13, 21]Nervous tension with racing thoughts and mental overactivity
Traditional herbalists specifically indicate passionflower for individuals who cannot 'switch off' their minds, who experience circular or repetitive anxious thoughts, and who have difficulty transitioning from a state of mental overactivity to rest. This is considered one of the most specific indications for passionflower in clinical herbal practice. The Eclectic physicians described it for 'the worry habit' and cerebral fullness.
[13, 14, 15]Cardiovascular System
Nervous palpitations and stress-related cardiac symptoms
Traditional use for heart palpitations driven by anxiety and nervous tension. The benefit derives from reduction of sympathetic nervous system overdrive and anxiolysis, not from direct cardiac effects. Often combined with Leonurus cardiaca (motherwort) or Crataegus spp. (hawthorn) in formulas targeting anxiety-associated palpitations.
[13, 14]Digestive System
Nervous dyspepsia and gastrointestinal spasm of nervous origin
The combination of antispasmodic and nervine actions makes passionflower appropriate for digestive complaints driven by anxiety and nervous tension — 'nervous stomach,' stress-related cramping, and functional gastrointestinal disorders with a strong psychological component. Traditionally combined with Matricaria recutita (chamomile) and Melissa officinalis (lemon balm) for nervous digestive complaints.
[2, 13]Musculoskeletal System
Muscle tension and spasm associated with stress
Traditional use for musculoskeletal tension and cramping associated with nervous tension. The antispasmodic and nervine relaxant actions combine to address stress-driven muscular holding patterns. Often used in formulas with Valeriana officinalis (valerian) and Piper methysticum (kava) for tension-type conditions.
[13]Reproductive System
Dysmenorrhea with nervous component
Historical and traditional use for menstrual cramps, particularly when associated with nervous tension and emotional distress. The antispasmodic action on smooth muscle provides a rationale for this use. Traditionally combined with Viburnum prunifolium (black haw) or Actaea racemosa (black cohosh) in formulas for dysmenorrhea.
[13, 15]Energetics
Temperature
cool
Moisture
slightly dry
Taste
Tissue States
wind/tension, heat/excitation
In traditional Western herbal energetics, passionflower is classified as cooling and slightly drying. It is specifically indicated for conditions arising from nervous tension (wind/tension tissue state) and heat/excitation of the nervous system. The cooling quality makes it suitable for individuals who are 'running hot' — agitated, restless, with a sense of internal heat from stress. The bitter taste reflects its flavonoid content and contributes to a gentle grounding and calming effect. The aromatic quality is mild but present, reflecting the volatile constituents. Unlike warming nervines such as valerian, passionflower is well-suited for individuals with warm, excess constitutions who are over-stimulated and tense. It is often compared to valerian: where valerian is warming and dispersing, passionflower is cooling and settling. This makes passionflower a more appropriate choice when nervous tension is accompanied by heat signs (irritability, flushing, inflammatory processes). Combines well with other cooling nervines such as lemon balm (Melissa officinalis) and with warmer nervines like valerian for a balanced formula.
Traditional Uses
Native American medicine
- Cherokee used a root infusion for boils, cuts, earache, and as a general tonic
- Cherokee applied a poultice of the root to inflammation and skin wounds
- Houma used the root as a blood tonic and for liver complaints
- Several southeastern tribes used the plant (root and leaf) as a general calming agent
- The fruit (maypop) was eaten as food by numerous southeastern tribes
"Passiflora incarnata has a long history of use among Native American peoples of the southeastern United States. The Cherokee used a root infusion for a variety of ailments, including boils, inflammation, and earache. The Houma used it as a blood tonic. The name 'maypop' derives from an Algonquian word or from the popping sound the fruit makes when crushed. While the primary documented ethnobotanical uses among Native Americans centered on the root rather than the aerial parts now used in Western herbalism, the recognition of the plant's calming and healing properties predates European contact."
Eclectic medicine (19th-early 20th century American)
- Insomnia, particularly from worry, overwork, or exhaustion
- Nervous irritability and restlessness
- Neuralgia (nerve pain)
- Infantile and pediatric nervous irritability and sleeplessness
- Epilepsy and convulsions (as adjunct treatment)
- Dysmenorrhea and menstrual irritability
- Tetanus (as symptomatic treatment for muscle spasm)
- Diarrhea of nervous origin
- Morphine and alcohol withdrawal symptoms
"The Eclectic physicians of the 19th and early 20th century were among the most enthusiastic advocates for Passiflora incarnata. Phares (1867) introduced it to Eclectic practice. King's American Dispensatory (Felter and Lloyd, 1898) describes passionflower as a pure nervous sedative, specifically indicated for 'the worry habit,' sleeplessness from overwork or exhaustion, and neuralgia. The Eclectics valued it particularly for its ability to calm without narcosis — promoting natural sleep rather than drugged stupor. Ellingwood (1919) described it as 'the remedy for that class of conditions where the patient worries and frets, where restless, nervous excitability prevails, where there is a tendency to convulsive manifestations.' It was also used as a supportive agent during withdrawal from opiates and alcohol."
European phytotherapy (20th century onward)
- Nervous restlessness and agitation (Commission E approved indication)
- Mild symptoms of mental stress (EMA well-established use)
- Sleep aid for mild insomnia (EMA well-established use)
- Component of numerous registered combination sedative and anxiolytic preparations across Europe
- Nervous cardiac complaints (often in combination with hawthorn)
"Passionflower became integrated into European phytotherapy in the early 20th century after its adoption from American Eclectic medicine. It received a positive German Commission E monograph in 1985 for nervous restlessness. The European Medicines Agency (EMA) recognizes it for well-established use in the relief of mild symptoms of mental stress and as an aid to sleep. It is one of the most widely prescribed sedative herbs in Europe, frequently appearing in combination products with valerian, hops, and lemon balm. The European Pharmacopoeia includes a monograph for Passiflorae herba standardized to total flavonoid content."
Brazilian traditional medicine
- Sedative and calming agent (calmante)
- Anxiety and nervousness
- Insomnia
- Neuralgia
- Hysteria and nervous excitability
"In Brazil, both P. incarnata and the native P. alata (maracuja-doce) are widely used in traditional medicine as sedatives and calmantes (calming agents). Passionflower preparations are popular in Brazilian folk medicine and pharmacy for anxiety, insomnia, and nervous complaints. P. alata is listed in the Brazilian Pharmacopoeia. The association between the Passiflora genus and calming/sedative properties is deeply embedded in Brazilian popular medicine."
Modern Research
Passionflower versus oxazepam for generalized anxiety disorder
Randomized, double-blind clinical trial comparing Passiflora incarnata extract (45 drops/day of Passipy tincture) to oxazepam (30 mg/day) in 36 outpatients with generalized anxiety disorder (GAD) over 4 weeks.
Findings: Both passionflower and oxazepam significantly reduced Hamilton Anxiety Rating Scale (HAM-A) scores over the 4-week trial with no significant difference in efficacy between the two treatments. Notably, passionflower-treated subjects reported significantly less impairment of job performance compared to the oxazepam group (P < 0.01), suggesting less cognitive/psychomotor impairment. Onset of therapeutic effect was slower with passionflower than oxazepam during the first week.
Limitations: Very small sample size (n=36, 18 per group). Short treatment duration (4 weeks). Single preparation and dose. No placebo control arm — both groups received active treatment. The study design (equivalence without placebo) limits conclusions about absolute efficacy.
[6]
Passionflower tea and sleep quality in healthy adults
Randomized, double-blind, placebo-controlled crossover study evaluating the effect of passionflower tea (1 g of dried Passiflora incarnata per 250 mL cup, consumed 1 hour before bedtime for 7 consecutive nights) on sleep quality in 41 healthy young adults (18-35 years) compared to placebo (parsley tea).
Findings: Subjective sleep quality, as measured by the Karolinska Sleep Quality Index from sleep diaries, was significantly improved during the passionflower tea week compared to placebo (P < 0.01). Polysomnographic data showed no statistically significant difference in objective sleep parameters (total sleep time, sleep onset latency, wake after sleep onset, sleep efficiency), though total sleep time showed a trend toward improvement. The improvement was modest but statistically and clinically meaningful for subjective experience of sleep quality.
Limitations: Healthy participants only (not insomnia patients). Short treatment duration (7 days). Modest dose (1 g tea). Polysomnographic measures did not reach statistical significance. Young adult population only. Parsley tea as placebo may not be perfectly taste-matched.
[7]
Passionflower as preoperative anxiolytic
Randomized, double-blind, placebo-controlled trial evaluating oral Passiflora incarnata (500 mg) given 90 minutes before ambulatory surgery for its effect on preoperative anxiety in 60 patients undergoing inguinal hernia repair.
Findings: Patients in the passionflower group had significantly lower anxiety scores (measured by numerical rating scale) compared to placebo at the time of arrival in the operating room (P < 0.001). Passionflower did not significantly affect sedation scores, hemodynamic parameters, or psychomotor function, suggesting anxiolysis without excessive sedation. Recovery parameters were similar between groups.
Limitations: Single dose assessment. Specific surgical population. Relatively small sample size (n=60, 30 per group). Single-center study. Self-report anxiety measure.
[8]
Review of Passiflora incarnata pharmacology and clinical evidence
Comprehensive review examining the phytochemistry, pharmacology, and clinical evidence for Passiflora incarnata, with emphasis on distinguishing evidence-based claims from unsupported assertions.
Findings: The review identified C-glycosyl flavonoids as the primary active constituents and confirmed that the alkaloid content of P. incarnata is too low to contribute meaningfully to pharmacological effects at normal doses. GABAergic mechanisms (GABA-A receptor modulation by flavonoids, possible GABA reuptake inhibition, presence of GABA in the plant) were identified as the most likely mechanism of action. Clinical evidence was assessed as promising but limited, with a need for larger, well-designed RCTs. The review confirmed the favorable safety profile and low toxicity.
Limitations: Narrative review (not systematic). Some of the clinical studies reviewed had methodological limitations. The authors noted the need for standardization of extracts used in clinical trials.
[17]
Safety and pharmacovigilance review of Passiflora incarnata
Comprehensive pharmacovigilance review of safety data for Passiflora incarnata, including clinical trial adverse event reports, case reports, and toxicological data.
Findings: The review found a very favorable safety profile for P. incarnata at recommended doses. Adverse effects reported in clinical trials were generally mild and similar to placebo (headache, dizziness, drowsiness). Rare case reports of possible adverse events included vasculitis (one case), altered consciousness with nausea (one case in a combination product), and possible hepatotoxicity (one case in a multi-herb product, causality uncertain). No reports of serious toxicity with monotherapy at standard doses. The authors concluded that P. incarnata can be considered safe when used appropriately.
Limitations: Narrative review dependent on spontaneous reporting systems, which underestimate true adverse event rates. Most case reports involved combination products, making attribution difficult. Limited long-term safety data.
[18]
Passionflower for dental anxiety
Randomized, double-blind, placebo-controlled trial evaluating Passiflora incarnata (260 mg extract) compared to midazolam (15 mg) and placebo for conscious sedation during mandibular third molar extraction in 40 patients.
Findings: Passionflower extract produced anxiolysis comparable to midazolam in terms of patient-reported anxiety reduction. Patients receiving passionflower experienced less amnesia and fewer psychomotor impairments compared to midazolam. The anxiolytic effect of passionflower was significantly greater than placebo.
Limitations: Small sample size (n=40). Specific dental procedure context. Single-dose comparison. Single-center study.
[10]
Passionflower for opiate withdrawal symptoms
Randomized, double-blind clinical trial comparing Passiflora incarnata extract (60 drops/day) plus clonidine (0.8 mg/day maximum) to clonidine alone (0.8 mg/day maximum) for management of outpatient opiate detoxification in 65 opiate-dependent patients over 14 days.
Findings: The passionflower plus clonidine combination was significantly superior to clonidine alone in managing mental symptoms of opiate withdrawal (anxiety, insomnia, irritability, agitation) as measured by the Short Opiate Withdrawal Scale mental symptoms subscore (P < 0.001). Physical symptoms were equally managed by both treatments. The study suggested passionflower as a useful adjunct to standard opiate withdrawal protocols, specifically for the psychological and sleep-related symptoms.
Limitations: Modest sample size (n=65). Combination treatment (passionflower added to clonidine, not tested alone). Open-label for the passionflower component in some reports. Short follow-up. Single center.
[9]
Systematic review and meta-analysis of passionflower for anxiety
Systematic review examining randomized controlled trials of Passiflora incarnata for anxiety disorders and preoperative/procedural anxiety.
Findings: The limited number of available RCTs showed a consistent pattern of anxiolytic effect for passionflower compared to placebo. The evidence was considered promising but insufficient for definitive conclusions due to the small number of trials and small sample sizes. The favorable safety profile was consistently demonstrated across studies.
Limitations: Few RCTs available. Small total participant numbers. Heterogeneity in preparations and dosing. The review highlighted the need for larger, multi-center trials with standardized extracts.
Preparations & Dosage
Infusion (Tea)
Strength: 1-2 g dried herb per 150-250 mL water
Pour 150-250 mL of boiling water over 1-2 g (approximately 1-2 teaspoons) of dried passionflower aerial parts. Cover and steep for 10-15 minutes. Strain. The infusion has a mildly bitter, slightly grassy flavor that is generally well-accepted.
One cup (150-250 mL) up to 3-4 times daily. For sleep: one cup 30-60 minutes before bedtime. For anxiety: 1 cup 2-4 times daily as needed.
For sleep: single dose before bedtime. For anxiety/restlessness: 2-4 times daily. For acute situational anxiety: one dose 30-90 minutes before stressful event.
May be used for 2-4 weeks initially. EMA recommends consulting a healthcare provider if symptoms persist beyond 2 weeks. Long-term use at standard doses appears safe based on traditional practice.
Children 6-12 years: half adult dose (0.5-1 g per cup) under professional guidance. Not recommended for children under 6 years.
The most traditional and simplest preparation. The Ngan and Conduit (2011) sleep study used a tea preparation (1 g per cup). The mild, slightly bitter flavor is more palatable than many herbal teas (much more acceptable than valerian). Can be combined with other calming herbs: Melissa officinalis (lemon balm), Matricaria recutita (chamomile), Tilia spp. (linden), or Lavandula angustifolia (lavender). EMA and WHO recommended preparation.
Tincture
Strength: 1:5, 45-60% ethanol (dried herb) or 1:2, 45% ethanol (fresh herb)
Macerate dried passionflower aerial parts in ethanol-water menstruum. Typical ratio 1:5 in 45-60% ethanol for dried herb, or 1:2 in 45% ethanol for fresh herb. Macerate for 2-4 weeks, shaking regularly. Press and filter.
1-4 mL (approximately 20-80 drops) up to 3 times daily. For sleep: 2-4 mL 30-60 minutes before bedtime. For acute anxiety: 1-2 mL as needed, up to every 2-3 hours. EMA: up to 4 mL of 1:8 tincture (ethanol 25%), 1-3 times daily.
For sleep: 1-2 doses in the evening. For anxiety: up to 3 times daily. For acute use: as needed up to every 2-3 hours.
2-4 weeks initially. Reassess if symptoms persist.
Under professional guidance only. Children 6-12: 0.5-1 mL up to 3 times daily.
Tinctures provide a convenient dosage form with rapid absorption and flexible dosing. The Akhondzadeh et al. (2001) GAD trial used a commercial tincture preparation (Passipy, 45 drops/day). Tinctures extract both water-soluble C-glycosyl flavonoids and lipophilic constituents. The alcohol content is appropriate for extracting the full range of active compounds.
capsule-powder
Strength: Dried herb: 400-900 mg per capsule. Standardized extracts: various DERs (typically 4-8:1), standardized to total flavonoid content.
Dried, powdered passionflower aerial parts in gelatin or vegetable capsules. Ensure product is from a reputable manufacturer with quality control for flavonoid content.
200-900 mg of dried herb powder or equivalent extract, up to 3 times daily. EMA: 0.5-2 g of herbal substance, 1-4 times daily. For standardized extracts: follow manufacturer's guidelines based on extract ratio.
For sleep: single dose 30-60 minutes before bedtime. For anxiety: divided doses 2-3 times daily.
2-4 weeks for initial assessment.
Not recommended for children under 12 years for self-medication.
Capsules bypass taste considerations. The Movafegh et al. (2008) preoperative anxiety study used 500 mg of Passiflora incarnata orally. Standardized extract capsules provide the most consistent dosing for clinical use.
Standardized Extract
Strength: DER 3-8:1 (extraction solvent ethanol 25-70%). Standardized to minimum 1.5% total flavonoids expressed as vitexin (European Pharmacopoeia requirement for the herbal substance).
Commercially prepared dry or liquid extracts standardized to total flavonoid content (expressed as vitexin). Various extraction methods and concentration ratios are available. Follow manufacturer's specific dosing guidelines.
Varies by product and extract ratio. EMA: dry extract (DER 3-8:1, extraction solvent ethanol 25-70%), up to 300 mg per dose, 1-4 times daily. Typical clinical trial doses have ranged from 200-500 mg extract per dose.
For sleep: 1-2 doses in evening/at bedtime. For anxiety: divided doses 2-4 times daily.
2-4 weeks initially.
Not established for most standardized products.
Standardized extracts provide the most consistent and reproducible dosing. Products used in clinical trials have varied considerably, which contributes to heterogeneity in the evidence base. When selecting a commercial product, look for standardization to flavonoid content per the European Pharmacopoeia monograph and third-party quality testing.
Glycerite
Strength: 1:5, 60% glycerin
Macerate dried or fresh passionflower aerial parts in vegetable glycerin-water mixture (typically 60-75% glycerin). Glycerites are alcohol-free alternatives suitable for those avoiding alcohol and for children under professional guidance.
3-5 mL up to 3-4 times daily.
For sleep: 1-2 doses in evening. For anxiety: up to 3-4 times daily.
2-4 weeks initially.
Under professional guidance. Children 6-12: 1-2 mL up to 3 times daily.
Glycerites provide an alcohol-free alternative with a sweet, palatable taste, making them suitable for children and those avoiding alcohol. Glycerin is a less efficient solvent than ethanol for some constituents, but it extracts the water-soluble C-glycosyl flavonoids adequately. A good option for pediatric use under practitioner supervision.
[13]
Syrup
Strength: Variable based on preparation method
Prepare a strong infusion or decoction of passionflower aerial parts, then combine with equal parts honey or sugar to create a syrup. Alternatively, add passionflower tincture to a simple syrup base. Store refrigerated.
5-10 mL (1-2 teaspoons) up to 3 times daily.
As needed for calming, up to 3 times daily.
Short-term use. Refrigerated syrup keeps for 2-4 weeks.
Under professional guidance. Children 6-12: 2.5-5 mL up to 3 times daily.
Syrups provide a palatable dosage form particularly suitable for children (under professional guidance) and for those who find other forms unacceptable. The sweet taste helps with compliance. Often combined with other calming herbs in compound syrups.
[13]
Safety & Interactions
Class 1
Can be safely consumed when used appropriately (AHPA Botanical Safety Handbook)
Contraindications
Although allergic reactions to passionflower are very rare, patients with known sensitivity should avoid all preparations.
EMA: not recommended for children and adolescents under 12 years for self-medication due to insufficient data. However, passionflower has a history of use in children under professional herbal practitioner supervision, and the Eclectic physicians specifically valued it for childhood nervousness and sleep difficulties. Use in children 6-12 under professional guidance is considered acceptable by many practitioners.
Drug Interactions
| Drug / Class | Severity | Mechanism |
|---|---|---|
| Benzodiazepines (diazepam, lorazepam, alprazolam, midazolam, oxazepam, etc.) (Benzodiazepines / CNS depressants) | moderate | Both passionflower flavonoids and benzodiazepines modulate GABA-A receptor function. Chrysin and other flavonoids bind at or near the benzodiazepine site, potentially producing additive CNS depressant effects. |
| Sedative-hypnotic medications (zolpidem, zaleplon, eszopiclone, suvorexant) (Sedative-hypnotics) | moderate | Potential additive CNS depression through overlapping mechanisms affecting sleep architecture and arousal. |
| Barbiturates (phenobarbital, etc.) and general anesthetics (CNS depressants / Anesthetics) | moderate | Potential additive CNS depression through shared GABAergic mechanisms. |
| Anticoagulants and antiplatelet agents (warfarin, heparin, aspirin, clopidogrel) (Anticoagulants / Antiplatelets) | theoretical | Theoretical concern based on the presence of coumarins (scopoletin, umbelliferone) in passionflower. Coumarin content is low and the clinical relevance is uncertain. |
| MAO inhibitors (phenelzine, tranylcypromine, selegiline, isocarboxazid) (Monoamine oxidase inhibitors) | theoretical | Early literature raised concern about harman-type alkaloids with MAO inhibitory activity. However, modern phytochemical analysis has established that alkaloid content in P. incarnata is trace and does NOT produce clinically significant MAO inhibition at standard doses. |
| Alcohol (ethanol) (CNS depressants) | minor | Potential additive CNS depression through shared GABAergic mechanisms. |
Pregnancy & Lactation
Pregnancy
possibly unsafe
Lactation
insufficient data
PREGNANCY: Classified as possibly-unsafe during pregnancy. Animal studies have demonstrated uterotonic (uterine-stimulating) activity of passionflower extracts at high doses, raising concern about potential to stimulate uterine contractions. The harman and harmaline alkaloids, though present only in trace amounts, have demonstrated uterine stimulant activity in vitro. The cyanogenic glycoside gynocardin, though present at low levels, is an additional theoretical concern. EMA recommends against use during pregnancy due to insufficient safety data. AHPA Botanical Safety Handbook classifies it as Class 2b (not to be used during pregnancy) based on animal data and traditional cautions. No adequate human studies during pregnancy. The Eclectic physicians used passionflower during pregnancy for nervousness, but modern regulatory guidance is more cautious. LACTATION: Insufficient data. Not known whether constituents pass into breast milk. EMA recommends against use during breastfeeding due to lack of data.
Adverse Effects
References
Monograph Sources
- [1] German Commission E (Bundesinstitut fur Arzneimittel und Medizinprodukte). Commission E Monograph: Passiflorae herba (Passion Flower Herb) -- Positive. Bundesanzeiger (Federal Gazette) (1985)
- [2] World Health Organization. WHO Monographs on Selected Medicinal Plants, Volume 3: Herba Passiflorae. World Health Organization, Geneva (2007) : 257-267
- [3] Committee on Herbal Medicinal Products (HMPC), European Medicines Agency. European Union Herbal Monograph on Passiflora incarnata L., herba. European Medicines Agency (2014)
- [4] ESCOP (European Scientific Cooperative on Phytotherapy). ESCOP Monographs: Passiflorae herba -- Passion Flower. Thieme, Stuttgart (2003) : 361-369
- [5] Gardner Z, McGuffin M (eds.). American Herbal Products Association's Botanical Safety Handbook, Second Edition. CRC Press, Boca Raton (2013) : 648-651
Clinical Studies
- [6] 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) ; 26 : 363-367 . DOI: 10.1046/j.1365-2710.2001.00367.x . PMID: 11679026
- [7] 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 (2011) ; 25 : 1153-1159 . DOI: 10.1002/ptr.3400 . PMID: 21294203
- [8] 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 (2008) ; 106 : 1728-1732 . DOI: 10.1213/ane.0b013e318172c3f9 . PMID: 18499602
- [9] 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) ; 26 : 369-373 . DOI: 10.1046/j.1365-2710.2001.00366.x . PMID: 11679027
- [10] Dantas LP, de Oliveira-Ribeiro A, de Sousa-Rodrigues DB, de Lucena-Batista L. Effects of Passiflora incarnata and midazolam for control of anxiety in patients undergoing dental extraction. Med Oral Patol Oral Cir Bucal (2017) ; 22 : e95-e101 . DOI: 10.4317/medoral.21140 . PMID: 27918739
- [11] Aslanargun P, Cuvas O, Dikmen B, Aslan E, Yuksel MU. Passiflora incarnata Linneaus as an anxiolytic before spinal anesthesia. J Anesth (2012) ; 26 : 39-44 . DOI: 10.1007/s00540-011-1261-7 . PMID: 22048283
- [12] Kaviani N, Tavakoli M, Tabanmehr M, Havaei R. The efficacy of passiflora incarnata linnaeus in reducing dental anxiety in patients undergoing periodontal treatment. J Dent (Shiraz) (2013) ; 14 : 68-72 . PMID: 24724123
Traditional Texts
- [13] Hoffmann D. Medical Herbalism: The Science and Practice of Herbal Medicine. Healing Arts Press, Rochester, VT (2003) : 573-574
- [14] Mills S, Bone K. Principles and Practice of Phytotherapy: Modern Herbal Medicine. Churchill Livingstone, Edinburgh (2000) : 457-462
- [15] Felter HW, Lloyd JU. King's American Dispensatory (18th edition, 3rd revision): Passiflora. Ohio Valley Company, Cincinnati (1898)
- [16] Ellingwood F. American Materia Medica, Therapeutics and Pharmacognosy: Passiflora. Ellingwood's Therapeutist, Chicago (1919)
Pharmacopeias & Reviews
- [17] Appel K, Rose T, Fiebich B, Kammler T, Hoffmann C, Weiss G. Modulation of the gamma-aminobutyric acid (GABA) system by Passiflora incarnata L.. Phytother Res (2011) ; 25 : 838-843 . DOI: 10.1002/ptr.3352 . PMID: 21089181
- [18] Miroddi M, Calapai G, Navarra M, Minciullo PL, Gangemi S. Passiflora incarnata L.: ethnopharmacology, clinical application, safety and evaluation of clinical trials. J Ethnopharmacol (2013) ; 150 : 791-804 . DOI: 10.1016/j.jep.2013.09.047 . PMID: 24140586
- [19] Dhawan K, Dhawan S, Sharma A. Passiflora: a review update. J Ethnopharmacol (2004) ; 94 : 1-23 . DOI: 10.1016/j.jep.2004.02.023 . PMID: 15261959
- [20] National Center for Complementary and Integrative Health (NCCIH). Passionflower. NCCIH, National Institutes of Health (2020)
- [21] Sarris J, McIntyre E, Camfield DA. Plant-based medicines for anxiety disorders, part 2: a review of clinical studies with supporting preclinical evidence. CNS Drugs (2013) ; 27 : 301-319 . DOI: 10.1007/s40263-013-0059-9 . PMID: 23653088
- [22] European Directorate for the Quality of Medicines (EDQM). European Pharmacopoeia Monograph: Passion Flower (Passiflorae herba). European Pharmacopoeia, Council of Europe, Strasbourg (2020)
Last updated: 2026-02-26 | Status: review