IngredientsCardinal Monkey Flower is a perennial flowering herb native to western North America. Its current accepted scientific name is Erythranthe cardinalis, and it is a flowering perennial in the family Phrymaceae. It was formerly known as Mimulus cardinalis, a name still in widespread use in horticulture, herbalism, and much of the botanical literature. Other synonyms and common names include Scarlet Monkey Flower, Scarlet Monkeyflower, Crimson Monkeyflower, Diplacus cardinalis, and Erythranthe cardinalis.
The reclassification from Mimulus to Erythranthe reflects significant taxonomic revision of the former Mimulus genus. Mimulus, also known as monkeyflowers, is a plant genus in the family Phrymaceae, which was traditionally placed in family Scrophulariaceae. The genus now contains only seven species, two native to eastern North America and the other five native to Asia, Australia, Africa, or Madagascar, as about 150 species that were once placed in the genus have since been assigned to other genera, the majority to genus Erythranthe. The botanical name has been changed to reflect recent research; Mimulus cardinalis is now Erythranthe cardinalis.
The genus name Erythranthe has classical roots: it comes from Greek erythros, "red," and anthos, "flower," as the only species in this genus when it was first published in 1840 by Édouard Spach being Erythranthe (Mimulus) cardinalis. The genus name Mimulus itself comes from the Latin diminutive of mimus, meaning a mimic, and the specific epithet cardinalis means scarlet or cardinal red.
There are several recognized variety-level synonyms within the historical species complex. These include Mimulus cardinalis var. exsul, var. griseus, var. rigens, and var. verbenaceus, as well as Mimulus verbenaceus.
It is important to note a critical taxonomic distinction that affects any discussion of supplement or ethnobotanical use. The "Mimulus" used in Bach Flower Remedies and identified as having the most well-documented ethnobotanical use is a different species — primarily Mimulus guttatus (yellow monkeyflower / seep monkeyflower) — not Erythranthe cardinalis. Where this article draws on Mimulus genus ethnobotany or remedy literature, the source species is identified explicitly.
Cardinal Monkey Flower is a creeping, herbaceous evergreen perennial of the figwort family that typically grows to 1–3 feet tall and as wide on upright, branched, sticky-hairy, yellowish-green flowering stems clad with opposite, sessile, sharp-toothed, downy, obovate, pale green leaves to 4½ inches long. Solitary, tubular, scarlet (rarely yellow) flowers (1–2 inches long) resembling snapdragons bloom from the leaf axils from June/July to October. Each flower has protruding stamens, bearded anthers, and a two-lipped corolla with a 2-lobed, sometimes-reflexed, upper lip and a 3-lobed lower lip.
Mimulus cardinalis is a fairly large, spreading, attractive plant which bears strongly reflexed, nectar-rich red or orange-red flowers. Occasional populations of yellow-flowered Mimulus cardinalis — which lack anthocyanin pigments in their corollas — are found in the wild.
This monkey flower is native to moist to wet places including streamsides, pond margins, springs, seepages, and under water-dripping cliffs, primarily in certain mountainous areas of Western North America from Washington south through Oregon, California, Utah, Nevada, Arizona, and New Mexico into northern Mexico. Mimulus cardinalis' range swoops through the west from Washington to New Mexico, preferring to grow in wet areas such as water's edge and moist rock faces, under elevations of 7,800 feet (2,400 m).
Its blooms and large nectar load attract hummingbirds, whose foreheads serve as the pollen transfer surface between flowers. Erythranthe cardinalis is cultivated in the horticulture trade and widely available as an ornamental plant for traditional gardens; natural landscape, native plant, and habitat gardens; and various types of municipal, commercial, and agency sustainable landscape projects.
This plant found in western states was one of the first western plants brought back to European gardens in the 1800s. The introduction of this species created a huge demand from gardeners obsessed with having western flowers.
Documented ethnobotanical evidence for Erythranthe cardinalis itself (as distinct from other monkeyflower species) as a medicinal or dietary plant is extremely limited in the peer-reviewed ethnobotanical literature. The primary scholarly sources on Native American ethnobotany, most notably the Native American Ethnobotany (NAEB) database compiled by Daniel Moerman — a mirror of the original NAEB database that compiles 45,000 uses of 4,000 different plants by 300 Native American Tribes, as recorded in 200 distinct sources, built over decades starting in the 1970s — document medicinal and food uses most extensively for related Mimulus species (particularly M. guttatus), with little documented use attributed specifically to M. cardinalis.
The Santa Monica Mountains reference sources note that the Chumash ethnobotany text by Jan Timbrook, Chumash Ethnobotany: Plant Knowledge Among the Chumash People, records uses for local monkeyflower species. However, no peer-reviewed source reviewed for this article specifically records Erythranthe cardinalis as a medicinal plant used by a named tribe for a named condition. Any such claims encountered in non-academic supplement marketing should be treated with caution.
The broader Mimulus genus, especially Mimulus guttatus (yellow monkeyflower, seep monkeyflower), has substantial documented use by multiple Native American peoples. Many species in the genus Mimulus were used as food or as medicine by First Peoples. The following ethnobotanical records are sourced from the NAEB database for Mimulus guttatus, not E. cardinalis:
Additionally, the Miwok and Pomo Native Americans used a monkeyflower species to treat minor ailments such as sores, burns, diarrhea, and eye irritation, and used the colorful flowers for decorative purposes. These records are associated with Mimulus aurantiacus (bush monkeyflower), again underscoring that uses documented in the ethnobotanical record typically pertain to other species within the genus rather than to E. cardinalis specifically.
In the 20th-century European complementary medicine tradition, a "Mimulus" flower remedy — prepared from Mimulus guttatus, not from Erythranthe cardinalis — became one of the most widely used products in the Bach Flower Remedy system. Bach flower remedies (BFRs) are a widely available, popular form of complementary and alternative medicine (CAM) developed in the 1930s by the British physician Dr. Edward Bach, who devoted his life to the discovery of 38 remedies that correspond to 38 negative emotional states. Initially, Dr. Edward Bach had named the yellow mimulus flowers as Mimulus luteus; however, afterward they were identified as Mimulus guttatus.
In the Bach system, Mimulus is used as a type or personality remedy for those who tend generally to be nervous, timid, and shy — who might blush easily or stammer — and is described as the remedy for known fears: whenever one is frightened or anxious about something specific and can name that something, Mimulus is prescribed. Mimulus fears are characterized as those of everyday life: fear of public speaking, of the dark, of aggressive dogs, of illness and pain.
The preparation method is specific: the flower essence remedy Mimulus is prepared employing the sun method — locating a place where the plant grows in the wild beside a bright stream, collecting flowers from many different plants, and floating them on water in a bowl placed in sunlight.
The most extensively studied chemical constituents of Erythranthe cardinalis are its floral pigment compounds, which have been characterized primarily in the context of evolutionary biology and pollination research rather than in a pharmacological or nutritional context.
Mimulus cardinalis produces red flowers as a result of a combination of anthocyanins and carotenoids. Two major pigment types determine flower color in Mimulus: anthocyanins are responsible for the pink/purple color and carotenoids for the yellow; a combination of the two pigment types often results in red color, as in the petal lobes of M. cardinalis.
Both M. lewisii and M. parishii produce small, dispersed anthocyanin spots in the nectar guide area, slightly spreading to the lateral petals, whereas M. cardinalis produces longitudinal stripes that spread across all five petals. The molecular regulation of these pigments has been studied in detail at the genomic level. Previous studies of Mimulus species have identified an anthocyanin-activating R2R3-MYB transcription factor, NEGAN, and an R3-MYB anthocyanin repressor, RTO, that control the formation of dispersed anthocyanin spots.
Occasional populations of yellow-flowered Erythranthe cardinalis that lack anthocyanin pigments in their corollas are found in the wild. This involves two natural M. cardinalis populations with yellow flowers; M. cardinalis is typically red-flowered due to the combination of high concentrations of both anthocyanins and carotenoids.
Phytochemical investigation of the secondary chemistry of the Mimulus/Erythranthe genus — relevant to the broader context of supplement interest — has been conducted primarily on Mimulus guttatus. Mimulus guttatus (yellow monkeyflower) has long been a model plant species for studies in genetics, evolution, and ecology, including plant–animal interactions; nonetheless, exceedingly little was known about its secondary chemistry until researchers discovered that the foliage contains a diverse suite of phenylpropanoid glycosides (PPGs), a class of compounds with many known biological activities. Using H-1 and C-13 NMR and UV and MS chromatography techniques, five PPGs were positively identified from the leaves; four of these compounds occur in other species and one was previously undescribed. UV and high-resolution tandem MS data putatively identified 11 additional foliar compounds as PPGs.
In a related study using HPLC-MS/MS methodology, four flavonoid glycosides were identified in Mimulus material: quercetin-3-O-D-glucoside, quercetin-3-O-D-xyloside, kaempferol-3-O-D-xyloside, and quercetin-3-O-D-(6″-coumaroyl)-galactoside — detected and identified for the first time in this botanical material.
A study investigating patterns of genetic variation in phytochemical defenses (phenylpropanoid glycosides, PPGs) in Mimulus guttatus grew plants derived from several natural populations in a common greenhouse environment and found substantial variation in the constitutive multivariate PPG phenotype and in constitutive levels of individual phytochemicals within plants (among leaves of different ages), within populations (among full-sibling families), and among populations.
It is critical to note that these phytochemical findings pertain to Mimulus guttatus, not to Erythranthe cardinalis. No peer-reviewed phytochemical analysis specific to E. cardinalis leaf, stem, or root secondary chemistry was identified in the sources reviewed for this article. Extrapolation of these findings to E. cardinalis as a supplement ingredient cannot be scientifically supported at this time.
Floral volatile organic compounds (VOCs) in Mimulus have been studied in the context of pollinator preference: key scent compounds contribute to the attraction of bees to bee-pollinated Mimulus lewisii, compared to its hummingbird-pollinated sister species M. cardinalis. Hummingbird-pollinated flowers typically have lower scent emission than insect-pollinated flowers, linked to hummingbirds' poor scent perception and limited scent memory. Again, these findings are biological and evolutionary in framing; no pharmacological activity has been attributed to these volatiles in the context of human health supplementation.
A thorough review of peer-reviewed literature, government health databases (NIH, NCCIH, NLM), pharmacopeial monographs, and evidence-based reference sources (including PubMed/PMC) reveals no clinical trials, human studies, or formal systematic reviews evaluating Erythranthe cardinalis (Cardinal Monkey Flower) as a dietary supplement ingredient in isolation. The plant does not appear in NIH Office of Dietary Supplements fact sheets, NCCIH monographs, WHO monographs, European Pharmacopoeia monographs, ESCOP monographs, or German Commission E monographs as a recognized therapeutic botanical. Its use in commerce as a supplement or nutraceutical ingredient is therefore not backed by a formal evidence base of the type required by those bodies.
The two contexts in which "Mimulus" appears in the clinical and quasi-clinical literature are: (1) Bach Flower Remedies, which use Mimulus guttatus, not E. cardinalis; and (2) the ethnobotanical record of related species. Both are addressed below with full source attribution.
Evidence strength: Does not demonstrate efficacy beyond placebo.
Three RCTs of BFRs for students with examination anxiety and one RCT of BFRs for children with attention-deficit hyperactivity disorder (ADHD) showed no overall benefit in comparison to placebo. Due to the number and quality of the studies, the strength of the evidence is low or very low.
A systematic review published in Swiss Medical Weekly (Ernst, 2010) specifically examined the randomized controlled trial evidence for Bach Flower Remedies. All randomized clinical trials of flower remedies were included; seven such studies were located; all but one were placebo-controlled; all placebo-controlled trials failed to demonstrate efficacy. It is concluded that the most reliable clinical trials do not show any differences between flower remedies and placebos.
A separate systematic review (Thaler et al., 2009, published in BMC Complementary and Alternative Medicine) arrived at the same conclusion: most of the available evidence regarding the efficacy and safety of BFRs has a high risk of bias. Based on the reported adverse events, BFRs are probably safe. Few controlled prospective trials of BFRs for psychological problems and pain exist, and analysis of the four controlled trials indicates that there is no evidence of benefit compared with a placebo intervention.
One RCT noted in the literature (Walach et al., 2001, Journal of Anxiety Disorders) examined the efficacy of Bach Flower Remedies in test anxiety in a double-blind, placebo-controlled, randomized trial with partial crossover design. The study of efficacy in test anxiety (Walach, Rilling & Engelke, J Anxiety Disord., 2001 Jul–Aug; 15(4):359–66) found no significant difference between Bach Flower Remedy and placebo.
Another RCT (Pintov et al., 2005, European Journal of Paediatric Neurology) evaluated Bach Flower Remedies in children with ADHD in a prospective double-blind controlled study. The study "Bach flower remedies used for attention deficit hyperactivity disorder in children — a prospective double blind controlled study" (Pintov, Hochman, Livne, Heyman & Lahat, Eur J Paediatr Neurol., 2005; 9(6):395–8) likewise showed no significant benefit over placebo.
The U.S. FDA has stated that it is not aware of scientific evidence to support homeopathy as effective. Furthermore, as noted above, the "Mimulus" ingredient used in Bach remedies is Mimulus guttatus at a 5X homeopathic dilution, not Cardinal Monkey Flower (E. cardinalis).
Evidence strength: Traditional/historical only; no controlled human studies conducted.
The documented uses of related Mimulus species by Native American peoples — including analgesic steam baths, poultices for wounds, and gastrointestinal decoctions (see Section 3.2) — are ethnobotanical observations recorded in the NAEB database. None of these traditional practices have been subjected to controlled clinical trials. The specific preparation, mechanism, and efficacy of these traditional uses for M. guttatus and related species remain unvalidated in peer-reviewed clinical literature.
Based solely on the documented traditional and Bach Flower Remedy uses of the Mimulus genus (primarily M. guttatus), the following body systems and health areas have been traditionally associated with monkeyflower plants. These associations are presented as historical and traditional claims only, not as clinically validated indications for Erythranthe cardinalis specifically:
No human clinical trial dosages for Erythranthe cardinalis as an isolated supplement ingredient exist to report, as no such trials have been conducted. The following dosage information pertains strictly to the Bach Flower Remedy "Mimulus" (Mimulus guttatus at homeopathic dilution) as reported on product labeling cited in this review:
Ethnobotanical preparations of M. guttatus are described in the historical record as decoctions of leaves and stems (for steam baths and oral use) and poultices of crushed leaves, but no quantified dosages for these preparations are specified in the ethnobotanical literature reviewed.
Most of the available evidence regarding the efficacy and safety of BFRs has a high risk of bias; however, based on reported adverse events in six included trials, BFRs are probably safe. The primary safety consideration in commercially prepared Bach Flower Remedies is the alcohol content of the preparation. Ainsworths Bach Flower Essence preparations use brandy as a carrier, with an alcohol content of 40% by volume. Standard commercial preparations typically contain approximately 27% alcohol as an inactive ingredient.
No toxicology studies, interaction studies, pharmacokinetic data, or formal safety assessments for Erythranthe cardinalis as a consumed supplement were identified in the peer-reviewed literature. Horticultural and botanical sources describe the plant as presenting no serious problems in a garden context, but this does not constitute a human safety evaluation.
For any Mimulus-genus Bach Flower Remedy product, the high alcohol content of the carrier (typically brandy or grape alcohol at 27–40% v/v) is a relevant safety and interaction consideration for individuals who avoid or cannot tolerate alcohol, including those on medications with alcohol interactions, persons in recovery from alcohol use disorder, pregnant or breastfeeding individuals, and children. Product labeling recommends consulting a health professional before use if pregnant or breastfeeding, and seeking a doctor's advice before giving to children under 2.
Statements about these products have not been evaluated by the U.S. Food and Drug Administration, and the products are not intended to treat, mitigate, diagnose, or cure any disease. Claims for Bach Flower Remedies are based on traditional homeopathic practices used for centuries, not on accepted medical or scientific evidence, and the products have not been FDA evaluated.
It is important for any review of Cardinal Monkey Flower to acknowledge that the preponderance of scientific publications concerning Erythranthe cardinalis / Mimulus cardinalis are not pharmacological but evolutionary and ecological in nature. Together with other species in Mimulus section Erythranthe, it serves as a model system for studying pollinator-based reproductive isolation. Research has focused on anthocyanin pigmentation genetics, carotenoid biosynthesis pathways, floral trait evolution, and the molecular basis of hummingbird versus bee pollinator preference. Shifts between different animal pollinators often coincide with speciation events in flowering plants, correlating with transitions to hummingbird-related floral traits such as red pigmentation, more reflexed petal lobes, tubular corollas, and more abundant nectar. These research programs have produced a rich body of genomic and biochemical literature, but none of it pertains to human health outcomes.
The following table summarizes the quality of evidence for each context in which Cardinal Monkey Flower or closely related Mimulus species appear in the health and supplement literature:
Health conditions that Cardinal monkey flower may help support.
Body systems that Cardinal monkey flower may help support.
Go back