Across cultures and centuries, plants have served as companions to healing rituals. Long before controlled clinical trials, indigenous traditions around the world cultivated deep knowledge of how specific botanicals could calm the nervous system, open the heart, support dreaming, and ease the body through transformative experiences. In recent decades, the Western scientific community has begun to catch up—documenting the pharmacological mechanisms behind many of these ancient practices. Plant allies for psychedelic support is not a new topic!
At Functional Medicine for Mental Health, we don’t position ourselves as a psychedelic practice. But we recognize that a growing number of individuals are seeking out psychedelic-assisted treatments for depression, anxiety, PTSD, substance use disorders, and existential distress. Our clinical philosophy has always been that how you prepare your body and mind for any healing intervention matters enormously—and that the conditions for lasting change are built through nutrition, nervous system regulation, and intentional lifestyle practices.
This article explores a set of herbs—sometimes called “plant allies” in traditional contexts—that have scientific support for addressing the very conditions often treated with psychedelic medicines: anxiety, insomnia, nervous system dysregulation, cardiovascular stress responses, and low mood. The goal is not to prescribe a protocol, but to provide a science-informed overview for clinicians and individuals who are considering how to optimize both preparation and integration. Most of these herbs have not been studied specifically within a psychedelic treatment framework, and where they have, we note it. What they share is a rich ethnobotanical history, growing peer-reviewed support, and a plausible role in what Dr. Rosalind Watts has called building “fertile soil” for therapeutic change [1].
Why Herbal Support for Psychedelic Work Matters
The emerging clinical literature on psychedelic-assisted therapy consistently emphasizes the importance of set, setting, and the broader therapeutic container. Leading training programs in this space highlight that integration—the process of making meaning from and sustaining the benefits of psychedelic experiences—begins with preparation [2]. Dr. Will Van Derveer, a pioneer in integrative psychiatry, has argued that durable psychedelic therapy outcomes depend on addressing the body alongside the psyche, noting that functional medicine, nutrition, and lifestyle interventions can fortify both the preparation and integration phases [3].
From a functional medicine perspective, this is intuitive. Anxiety disorders, mood disturbances, chronic pain, and trauma-related conditions all involve dysregulation across multiple biological systems—neuroendocrine, immune, gastrointestinal, and autonomic. Herbal medicines, when grounded in evidence, offer a way to gently modulate these systems without the dependency profiles or cognitive side effects of many pharmaceutical agents. For individuals approaching psychedelic work, this kind of nervous system support can reduce pre-session anxiety, improve sleep quality during vulnerable periods, ease cardiovascular stress responses, and provide gentle grounding during the often-challenging integration window.
It’s worth noting that many indigenous traditions never separated “preparation” and “integration” from everyday living. Working with plant medicines in those contexts was embedded within a worldview that included community, nutrition, relationship with the natural world, and reverence for the plants themselves. As we bridge traditional wisdom and clinical science, we honor that broader context while rigorously examining the evidence.
Herbs with Strong Peer-Reviewed Evidence
The following herbs have the most robust scientific literature supporting their use for the conditions commonly treated in psychedelic therapy contexts. These are not “psychedelic herbs” per se—they are well-studied botanicals with mechanisms relevant to preparation and integration.
Passionflower (Passiflora incarnata)
The Science
Passionflower is among the most well-studied anxiolytic herbs in the Western pharmacopeia. A 2020 systematic review of nine randomized clinical trials found that the majority of studies reported significant reductions in anxiety following passionflower administration, with a favorable safety profile and no adverse effects on memory or cognitive function [4]. The plant’s mechanism involves multiple neurotransmitter systems: GABAergic modulation through inhibition of GABA-transaminase, interactions with serotonin pathways, and effects on brain-derived neurotrophic factor (BDNF) [5]. A 2024 randomized, double-blind, placebo-controlled trial demonstrated that a standardized passionflower extract significantly reduced perceived stress and improved sleep quality and general psychological health over 30 days [6].
Traditional and Clinical Applications
In herbal medicine traditions, passionflower is classified as a nervine, hypnotic, sedative, antispasmodic, and mild antidepressant. It is commonly recommended for racing circular thoughts, panic-like overstimulation of the nervous system, burnout, restlessness, and exhaustion. Practitioners also note its capacity to support connection with intuition and the subconscious mind—qualities that may be particularly relevant during psychedelic integration. Application forms include tincture, tea, smoking blends, and flower essences. Its MAO-inhibiting activity, while mild, is a clinically important consideration when combining with serotonergic psychedelics [5].
Kava (Piper methysticum)
The Science
Kava has one of the strongest evidence bases of any anxiolytic herb. A 2018 systematic review and meta-analysis of clinical trials for generalized anxiety disorder found that kava demonstrated a moderate-to-large effect size (0.59–0.99) compared to placebo across multiple trials [7]. The active kavalactones modulate GABA activity, inhibit monoamine oxidase B, inhibit norepinephrine and dopamine reuptake, and influence limbic system function [8]. Notably, a meta-analysis of ten human trials confirmed that kava extracts have no negative effect on cognitive function—unlike many pharmaceutical anxiolytics [9]. The hepatotoxicity concerns that led to European bans in the early 2000s have been substantially addressed by subsequent research, with the German ban overturned by court ruling based on re-evaluation of the evidence [8].
Traditional and Clinical Applications
In Pacific Island cultures, kava has been used for over 1,500 years to promote psychological and physical relaxation in ceremonial and healing contexts. It is traditionally associated with enhancing connection and communication while breaking down interpersonal barriers—qualities that may be relevant for individuals working through relational trauma. The plant is classified as anxiolytic, sedative, hypnotic, and antispasmodic. It is particularly indicated for individuals processing trauma (including sexual trauma), those with anxiety-related insomnia, social withdrawal, and somatic tension. Given its MAO-B inhibitory activity, clinicians should be aware of potential interactions with serotonergic compounds. Application forms include tea, tincture, capsules, and topical oil.
Lemon Balm (Melissa officinalis)
The Science
Lemon balm has been the subject of substantial pharmacological and clinical investigation. A 2021 systematic review and meta-analysis found promising evidence for its anxiolytic and antidepressant effects, particularly in acute settings [10]. The plant’s mechanism centers on GABA-transaminase inhibition via rosmarinic acid, effectively increasing GABA availability in the brain [11]. It also modulates cholinergic and serotonergic pathways, and preclinical research has shown it promotes hippocampal neurogenesis in a dose-dependent manner while reducing serum corticosterone [12]. A 2024 double-blind, placebo-controlled crossover study demonstrated that a standardized lemon balm phytosome significantly improved sleep quality, with a 15% increase in slow-wave sleep duration and 87% of participants reporting improved sleep versus 30% in the placebo group [13].
Traditional and Clinical Applications
In traditional herbal medicine, lemon balm is indicated as a calming nervine and mild antidepressant with particular affinity for the nervous and digestive systems. It is one of the herbs most commonly recommended for pre-experience nervous system support, helping to soothe an anxious mind without sedation at moderate doses. Lemon balm pairs well with other calming herbs like linden and rose. It has a long history in European folk medicine dating back to Paracelsus, who called it the “elixir of life.” Application forms include tea, tincture, and standardized extract.
American Skullcap (Scutellaria lateriflora)
The Science
American skullcap is one of the most widely prescribed herbs in Western herbal medicine for anxiety and nervous tension. Its key flavonoids—baicalin, baicalein, and wogonin—bind to the benzodiazepine site of GABA-A receptors, providing a mechanistic basis for its anxiolytic effects [14]. A preclinical study confirmed significant anxiolytic activity in animal models, with the plant also containing endogenous GABA (~1.6 mg/g) and glutamine (~31 mg/g) [14]. In a double-blind, placebo-controlled crossover study of 43 healthy volunteers, skullcap (350 mg three times daily) produced a highly significant improvement in Total Mood Disturbance (p < 0.001) without reduction in energy or cognition [15]. A 2025 randomized clinical trial further demonstrated that a skullcap extract-based supplement significantly improved sleep quality as measured by the Pittsburgh Sleep Quality Index [16].
Traditional and Clinical Applications
Skullcap has been used medicinally in North America since at least 1785 and is classified as a nervous system restorative and sedative. It is frequently recommended as a pre-experience nervous system support herb for individuals with heightened anxiety, restlessness, or difficulty relaxing before therapeutic sessions. Its action is gentle yet reliable, and it is considered safe for long-term use. Application forms include tincture, tea, and capsules.
Hawthorn (Crataegus spp.)
The Science
Hawthorn has one of the longest histories of medicinal use of any cardiovascular botanical, with modern research supporting its traditional applications. A 2025 meta-analysis of six randomized, placebo-controlled trials (428 participants) found that hawthorn statistically significantly decreased systolic blood pressure by an average of 6.65 mmHg [17]. Two Cochrane reviews and additional meta-analyses have documented its benefits in mild-to-moderate heart failure, including increased exercise tolerance, decreased cardiac oxygen consumption, and improved left ventricular ejection fraction [18]. The European Medicines Agency recognizes hawthorn leaf and flower as a traditional herbal medicine for temporary nervous cardiac complaints including palpitations and perceived extra heartbeats due to mild anxiety [17]. Its cardiovascular protective effects are attributed to flavonoids (hyperoside, quercetin) and oligomeric proanthocyanidins with potent antioxidant and vasodilating properties [18].
Traditional and Clinical Applications
Hawthorn is classified as cardiotonic, nervine, and antioxidant. In psychedelic preparation and integration contexts, hawthorn is particularly relevant for individuals whose anxiety manifests as cardiovascular symptoms—heart palpitations, chest tightness, blood pressure spikes, and difficulty breathing during stress responses. These somatic presentations are extremely common during psychedelic experiences, and hawthorn’s ability to regulate heart rhythm and reduce blood pressure provides a meaningful safety buffer. It combines well with linden, which shares cardiovascular-nervous system dual affinity. Application forms include tea, tincture, and standardized extract.
Herbs with Moderate or Emerging Evidence
The following herbs have growing but less extensive peer-reviewed literature. They are included because of their strong ethnobotanical traditions, plausible mechanisms, and clinical relevance to the preparation and integration process.
Rose (Rosa damascena)
The Science
Rosa damascena has been the subject of a rapidly expanding body of clinical research. A 2024 dose-response meta-analysis of 32 randomized controlled trials found that rose administration (primarily aromatherapy) significantly reduced state anxiety (SMD: –1.74, p < 0.001) as well as depression and stress symptoms in adults [19]. The plant’s anxiolytic effects are attributed to citronellol and 2-phenylethanol, while its antidepressant mechanisms involve serotonin reuptake inhibition and modulation of the ERK-CREB-BDNF signaling pathway [20]. A 2025 meta-analysis further confirmed these anxiolytic effects across multiple age groups and intervention durations, with additional benefits for sleep quality [21].
Traditional and Clinical Applications
Rose is described in traditional herbal medicine as an aphrodisiac, nervine, and reproductive tonic with anti-inflammatory and antioxidant actions. It is particularly indicated for individuals whose stress manifests as cardiovascular symptoms (elevated heart rate and blood pressure), and for those experiencing grief, sadness, difficulty with compassion, or emotional guardedness. In psychedelic integration, rose is considered a heart-opening ally—supporting self-love, easing fear, and facilitating openness to giving and receiving. Application forms include tea, tincture, aromatherapy, and smoking blends.
Blue Lotus (Nymphaea caerulea)
The Science
Blue lotus—sometimes called the “sacred narcotic lily of the Nile”—has a pharmacological profile that is increasingly well-characterized. It contains two primary alkaloids: apomorphine (a non-selective dopamine agonist with serotonin-modulating properties, including partial agonism at 5-HT1A and antagonism at 5-HT2A) and nuciferine (which shows a complex receptor profile including dopamine transporter inhibition, 5-HT2A antagonism, and anti-inflammatory effects potentially mediated through PPAR-delta activation) [22,23]. Preclinical research on the related species Nymphaea lotus demonstrated anxiolytic and antidepressant-like effects in validated animal models with increases in hippocampal BDNF [24]. However, robust human clinical trials remain limited, and safety concerns exist around higher-dose recreational use [25].
Traditional and Clinical Applications
Blue lotus has been used in Egyptian spiritual and healing traditions dating to the 14th century BCE, where it was depicted on tomb walls and papyri as a symbol of rebirth and spiritual awakening. In contemporary herbal practice, it is described as gently sedative, supporting deeper sleep, reducing nerve tension, and easing anxiety. It is also used to promote parasympathetic activation—shifting the body from vigilance into receptivity and rest. Practitioners associate blue lotus with both pre-experience support (insomnia and racing mind before a journey) and post-experience integration (sustaining spiritual connection). It supports lucid dreaming and dream recall. Application forms include tea (long infusion, 24+ hours), herbal smoke, tincture, and topical flower oil. Blue lotus warrants cautious use given its psychoactive alkaloid content.
Linden (Tilia spp.)
The Science
Linden flower has documented cardiotonic, carminative, diaphoretic, diuretic, and nervine properties. While human clinical trials specifically on linden are limited compared to the herbs above, preclinical evidence supports its traditional cardiovascular and anxiolytic applications. Its flavonoid content (particularly tiliroside, quercetin, and kaempferol) has demonstrated antioxidant and vasorelaxant effects [26]. Linden is pharmacopoeial in several European countries as a traditional remedy for nervous cardiac complaints and mild anxiety.
Traditional and Clinical Applications
Linden is traditionally indicated for stress and tension that manifest around the heart—heart palpitations, breathing difficulty, tightness, and sweating. Emotionally, it is considered an ally for fear that constricts the heart, particularly fear around revisiting old wounds—a common experience in psychedelic therapy. It eases agitation and anger and helps with surrender. Linden combines well with hawthorn (as a cardiotonic nervine), lemon balm, and rose. Application forms include tea and tincture.
Damiana (Turnera diffusa)
The Science
Damiana has documented nervine, analgesic, and mild antidepressant properties. Preclinical research has identified GABAergic activity and flavonoid-mediated anxiolytic effects [27]. It has traditionally been classified as both a relaxant and mild stimulant—a dual action sometimes described as “de-arming our defenses while energizing a burned-out nervous system.” Its aphrodisiac effects have been partially attributed to effects on nitric oxide pathways [27]. Clinical evidence remains primarily preclinical and ethnobotanical.
Traditional and Clinical Applications
Damiana is indicated for individuals who feel disconnected or numb from their desires, passions, sexuality, creativity, and overall sense of self. In the context of psychedelic work, this numbness and disconnection is often what brings people to seek treatment in the first place. Damiana is used both as a sensory and emotional pain-reliever, and as a plant that helps re-ignite warmth, desire, and the capacity for pleasure. It is particularly valued in integration for helping individuals reconnect with themselves and the world around them. Application forms include tea, tincture, and smoking blends.
California Poppy (Eschscholzia californica)
The Science
California poppy contains alkaloids distinct from opium poppy (Papaver somniferum) but with documented sedative, analgesic, and antispasmodic properties. Preclinical research has identified GABAergic modulation and benzodiazepine receptor binding as primary mechanisms [28]. The European Medicines Agency recognizes it as a traditional herbal medicine for mild anxiety and sleep disturbance. It is considered non-habit-forming and well-tolerated.
Traditional and Clinical Applications
Poppy (in the non-opiate species) is indicated for insomnia, restlessness, nervous agitation, muscle tension, spasms, and pain. For psychedelic work, it is considered particularly relevant for individuals who had emotionally intense journeys with high energetic output, and for those processing painful memories or trauma. Its action is dose-dependent—higher doses are more sedative—and the general recommendation is to start low. It supports the mind, body, and spirit during the often vulnerable integration window. Application forms include tea and tincture.
Pericón (Tagetes lucida)
The Science
Pericón, also known as Mexican tarragon or sweet mace, has documented antispasmodic, anxiolytic, and antimicrobial properties. Its essential oil contains estragole and methyl eugenol with demonstrated smooth muscle relaxant effects [29]. Preclinical studies have shown anxiolytic and antidepressant-like activity, with the plant’s mechanism thought to involve serotonergic and GABAergic systems [29]. Clinical evidence is predominantly ethnobotanical.
Traditional and Clinical Applications
In Mesoamerican traditional medicine, pericón is used for individuals who carry their stress and fears in the gut, disrupting digestion. It is classified as an aromatic relaxing nervine, carminative, and antispasmodic—easing tension in the body and spasms in the digestive tract. It is traditionally indicated for gas, bloating, and diarrhea related to anxiety. On a spiritual level, pericón is recommended for individuals experiencing susto—a concept in Latin American traditional medicine describing soul loss or fright sickness—and is used to clear and protect energy. For spirit work, it is employed in herbal baths, smoking blends, and smudging. For physical and nervous system support, tea or tincture is preferred.
Safety Considerations
This section is critically important. Several of the herbs discussed above have MAO-inhibiting properties (passionflower, kava) or complex receptor profiles (blue lotus). For individuals taking serotonergic medications—including SSRIs, SNRIs, or MAOIs—or planning psychedelic experiences with serotonergic compounds (psilocybin, ayahuasca, MDMA), these interactions must be carefully evaluated by a qualified healthcare provider.
Key safety principles include: (1) always disclose all herbal supplements to your prescribing clinician; (2) be aware that “natural” does not mean “without pharmacological activity”—these plants contain bioactive compounds with real effects on neurotransmitter systems; (3) quality and sourcing matter enormously, as adulteration and inconsistent potency are common in the supplement industry; and (4) certain herbs (particularly blue lotus and kava) have dose-dependent effects that can shift from therapeutic to problematic at higher doses.
We do not recommend Datura or Brugmansia, which appear in some traditional pharmacopeias, due to their significant toxicity profile and narrow therapeutic window. While they have legitimate ethnobotanical histories, their risk-benefit ratio does not support recommendation in a clinical context.
Conclusion
The herbs described in this article are not psychedelics. They are, however, pharmacologically active botanicals with peer-reviewed evidence supporting their use for the very conditions that bring people to psychedelic therapy—anxiety, insomnia, nervous system dysregulation, cardiovascular stress, low mood, and the somatic imprints of trauma. Whether used in the weeks before a psychedelic experience to build nervous system resilience, or in the days and weeks after to support emotional processing and grounding, these plants offer a bridge between ancient wisdom and modern clinical practice.
At Functional Medicine for Mental Health, we believe that the conditions for therapeutic change are built through intentional, multi-system support. The psychedelic experience may open a door—but it’s the daily practices of nutrition, sleep, movement, community, and yes, potentially herbal allies, that determine whether you can walk through it and stay on the other side.
If you are considering psychedelic-assisted therapy, or are in the process of integrating a past experience, we encourage you to work with a provider who can assess your individual needs, medication interactions, and goals. These herbs are not a replacement for professional care—but they may be a meaningful complement to it.
About the Author:
Dr. David Wiss, PhD, RDN, IFMCP, is a functional medicine practitioner specializing in treatment-resistant mental health conditions. His work integrates nutritional psychiatry, gut-brain medicine, and advanced functional testing to help patients address the root causes of depression, anxiety, and other psychiatric conditions.
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