IngredientsCynoglossum grande Douglas ex Lehm. (formerly the accepted botanical name) is now treated in current taxonomy as a synonym for Adelinia grandis (Douglas ex Lehm.) J.I. Cohen. The scientific name was formally changed in 2021 from Cynoglossum grande. In recent years, Cynoglossum grande Douglas ex Lehm. has been reclassified as Adelinia grandis (Douglas ex Lehm.) J.I. Cohen, based on phylogenetic work by botanist J.I. Cohen. According to Plants of the World Online (Kew Science), the name Cynoglossum grande is now a synonym of Adelinia grandis.
Adelinia grandis, previously known as Cynoglossum grande, is a species of flowering plant in the borage family known as Pacific hound's tongue, and it is the only species in the genus Adelinia.
Because the name Cynoglossum grande remains widely used in ethnobotanical literature, databases, herbaria records, and dietary supplement/natural product contexts, this article uses both names interchangeably, with the historically common form employed in headings for clarity.
The plant is known by several common names, including Houndstongue, Pacific Hound's Tongue, Western Hound's Tongue, and Grand Hound's Tongue.
Cynoglossum is a dicot genus of the Boraginaceae (borage family). The name Cynoglossum is derived from the Greek words cynos (of a dog) and glossa (tongue), depicting the texture and shape of the leaves in species of the genus, hence the common name "hound's tongue."
Cynoglossum is comprised of annuals (C. amabile), biennial or monocarpic perennial species (C. officinale), as well as long-lived herbaceous perennials (C. grande). Members of this genus have a worldwide distribution, with many species occupying temperate as well as tropical regions of the Old and New Worlds; the genus comprises approximately 80–90 to as many as 200 species depending on taxonomic authority.
Cynoglossum grande, or Pacific Hound's Tongue, is a non-invasive herbaceous perennial native to woodland habitats from British Columbia south to California. It is a perennial herb producing an erect stem 30 to 90 centimeters tall from a taproot. It produces an erect stem up to 80 centimetres (31 in) tall from a taproot. The leaves are mostly located around the base of the plant, each with an oval blade up to 15 cm (6 in) long held on a petiole, which near the base are also up to 15 cm long.
The flower cluster is a panicle of flowers on individual pedicels. Each five-lobed flower is bright to deep blue with white appendages at the center. It is 1 to 1.5 centimeters wide. The fruit is an array of four slightly bristly nutlets.
The plant begins its vegetative cycle in late winter, sending up hairy leaves which unfold somewhat like hairy rainbow chard, before sending up a flowering stalk to two feet. The flowers open magenta and turn vivid blue as they age. Five white appendages surround the base of each flower.
The plant grows from a modified rhizomatous taproot that can produce many rosettes from a single root system. It exhibits a marked summer dormancy, quickly retreating into dormancy when the ground dries up in its native summer-dry territory.
This species emerges in late winter with bronze leaves, appearing somewhat tongue-like, gradually turning green as they mature. The leaves are somewhat lance to heart-shaped, smooth above, and hairy below, clustering at the base of the plant.
The plant is native to western North America from British Columbia to California, where it grows in shady areas in woodland and chaparral. It is a perennial herb native to California and also found elsewhere in western North America. Typical habitat communities include Yellow Pine Forest, Mixed Evergreen Forest, and Northern Oak Woodland, generally on slopes.
Recent phylogenetic work involving both molecular and morphological markers has supported the conclusion that Old World and New World species aggregates form separate major clades within the tribe Cynoglosseae DC., leading to the more widespread acceptance of several segregate genera. In the New World, generally four or five species have been accepted in the taxonomic and floristic literature. In recent years, these have been reclassified into three generic segregates, including Cynoglossum grande Douglas ex Lehm. = Adelinia grandis (Douglas ex Lehm.) J.I. Cohen.
Cynoglossum grande, commonly known as Pacific hound's tongue, has a history of use among certain Native American groups for treating wounds and sores. The primary documentation of these uses comes from the systematic compilation of ethnobotanical records, most notably Daniel E. Moerman's Native American Ethnobotany database. The Native American Ethnobotany (NAEB) database compiles 45,000 uses of 4,000 different plants by 300 Native American Tribes, as recorded in 200 distinct sources. It was built over decades, starting in the 1970s, spearheaded by the work of Daniel Moerman.
Pacific Hound's Tongue was used by Native Americans, including the Concow, who would grate the roots and apply them as a burn dressing, and the Pomo, who would use the grated roots as a treatment for stomachaches. These records are cited from Daniel E. Moerman's Native American Ethnobotanical Database.
This usage is primarily based on traditional ethnobotanical practices rather than scientific validation. Ethnobotanical records, such as those compiled by Daniel E. Moerman, indicate that some Indigenous communities applied poultices made from the leaves of related Cynoglossum species to cuts, sores, or skin irritations.
Summarizing the documented preparations across these tribes:
The primary preparations documented in ethnobotanical sources for C. grande involve the root as the primary plant part used. Native Americans made a preparation of the roots to treat burns and stomach aches. The method described in ethnobotanical records involves grating or pounding the root material for topical application as a poultice or dressing, or ingestion for gastrointestinal complaints.
Ethnobotanical records, such as those compiled by Daniel E. Moerman, indicate traditional use among Indigenous communities; however, these reports are anecdotal and not backed by clinical trials or robust pharmacological studies specific to Cynoglossum grande.
It is important to note that the broader genus Cynoglossum, including the closely related species C. amabile and C. officinale, carries a considerably larger ethnomedicinal literature than C. grande alone, but the medicinal traditions of those species cannot be uncritically attributed to C. grande without specific documentation.
Cynoglossum grande belongs to a genus and family that is particularly rich in pyrrolizidine alkaloids (PAs). Pyrrolizidine alkaloids (PAs) are secondary plant constituents produced by a wide variety of plants, including those in the Asteraceae, Boraginaceae, and Fabaceae families. More than 500 different PAs have been identified in more than 6,000 plant species to date.
The genus Cynoglossum, distributed mainly in temperate regions, comprises approximately 75 species worldwide and is particularly rich in pyrrolizidine alkaloids (PAs), compounds known both for their hepatotoxicity and for their significant pharmacological activities within the genus.
The plant contains pyrrolizidine alkaloids, which are generally hepatotoxic and considered unsafe for internal use.
Although the specific PA profile of C. grande itself has not been comprehensively characterized in peer-reviewed literature (in contrast to the better-studied C. officinale and C. amabile), the chemical profiles of related species within the genus provide important comparative context. In the closely related species:
Pyrrolizidine alkaloids (PAs) are among the most common secondary metabolites isolated from Boraginaceae species.
Phytochemical studies in the Cynoglossum genus have identified the main chemical components as pyrrolizidine alkaloids (PAs), sterols, and organic acids or esters. Among these, PAs are the most abundant.
Beyond PAs, other Cynoglossum species have yielded additional compounds of interest. From Cynoglossum columnae, β-arbutin and pyrrolizidine alkaloid N-oxides were isolated from the aerial parts; echinatine N-oxide, rosmarinic acid, and 9″-methyl lithospermate were isolated from the root extract. Rosmarinic acid, a phenolic acid, and tannins represent a secondary chemical class found in related taxa. A total of 47 chemical components, including alkaloids (PAs), sterols, organic acids, and saccharides, have been isolated from the related species C. amabile.
Pyrrolizidine alkaloids (PAs) typically contain either a saturated or a 1,2-unsaturated necine base unit. PAs are generally classified into four types based on the necine bases that are present: platynecine, retronecine, heliotridine, and otonecine. Except for the otonecine-type alkaloids, the other alkaloids can form the N-oxides, which are also commonly found in PA-containing plants.
Modern research indicates that the most basic structural unit of PAs' toxicity is when there are double bonds at positions 1 and 2, and at least one hydroxyl group at position 7 or 9 is esterified. The toxicity of diesters is greater than that of monoesters, and macrocyclic diester PAs are more toxic than open-chain diesters.
Ingested pyrrolizidine alkaloids are converted to pyrrolic esters by hepatic cytochrome P450 enzymes. These esters are alkylating agents, which react with cytosolic and nuclear proteins and nucleic acids.
PAs are metabolized predominantly by hepatocytes through cytochrome P450 (CYP450)-mediated transformation to N-oxides and conjugated dienic pyrroles. These highly reactive, electrophilic pyrroles react with many biomolecules, such as glutathione (GSH), which facilitate excretion. The pyrroles can also combine with essential cellular proteins and nucleic acids, forming adducts that may damage cell function and homeostasis.
The formation of hepatic pyrrole–protein adducts, which directly correlated with the elevation of serum ALT activity, was identified as a common insult leading to PA-induced liver injury.
Pyrrolizidine alkaloids are produced as a defense mechanism against herbivorous pests and have been found to result in hepatotoxicity. They are believed to function against herbivores due to the proven inhibiting effect of some PAs on acetylcholinesterase activity.
For the genus Cynoglossum more broadly, and specifically for the well-studied C. amabile, the following pharmacological activities have been identified in laboratory research: pharmacological studies show that the chemical extracts of C. amabile possess various biological activities, such as anti-inflammatory, anti-tumor, anti-microbial, cardiovascular effects, ganglionic action, and acetylcholinesterase inhibition. These findings relate to C. amabile and cannot be directly extrapolated to C. grande without species-specific evidence.
The plant contains pyrrolizidine alkaloids, which are generally hepatotoxic and considered unsafe for internal use; however, their topical safety and efficacy have not been well studied. There is currently no substantial scientific literature demonstrating wound healing or antimicrobial properties for C. grande or its extracts.
The traditional uses of C. grande are anecdotal and not backed by clinical trials or robust pharmacological studies specific to Cynoglossum grande. No human clinical trials, randomized controlled trials, systematic reviews, or meaningful in vitro/in vivo studies specific to Cynoglossum grande were identified in peer-reviewed literature. The following subsections must therefore be understood in the context of related species data and genus-level evidence only.
Evidence level: Traditional use only; no clinical or preclinical studies specific to C. grande.
Cynoglossum grande has a history of use among certain Native American groups for treating wounds and sores, but this usage is primarily based on traditional ethnobotanical practices rather than scientific validation.
For other members of the genus, there is limited preclinical research. Studies on C. clandestinum, a North African species, found that HPLC-DAD identified quercetin-3-glucoside and epicatechin as major constituents, and the extract showed strong antioxidant and dose-dependent anti-inflammatory activities in laboratory models. However, these findings are specific to C. clandestinum, are in vitro or animal-based, and cannot be used to infer efficacy for C. grande.
Evidence level: Traditional use only; no clinical or preclinical studies specific to C. grande.
The Pomo people used grated roots as a treatment for stomachaches. This use is documented ethnobotanically but has not been subject to any pharmacological investigation for C. grande.
Evidence level: Traditional use only; no clinical or preclinical studies specific to C. grande.
The Concow people grated the roots and applied them as a burn dressing. No laboratory or clinical data exist to verify or characterize any putative wound-healing or burn-treatment activity for this species.
While no clinical research exists for C. grande, research on other Cynoglossum species provides contextual information. For C. amabile: it is important to note that C. amabile exhibits hepatotoxicity, with its toxicity being linked to its primary PA components. Although preliminary studies suggest potential applications in the treatment of prostate diseases and alopecia, further research is needed to validate these clinical uses. These preliminary findings relate to C. amabile in Asian traditional medicine contexts and are not specific to C. grande.
Based exclusively on documented ethnobotanical records, the following body systems and health areas have been associated with traditional use of C. grande:
No standardized dosage forms exist for Cynoglossum grande as a dietary supplement or botanical medicine in any regulatory framework identified. The plant is not listed in current editions of the United States Pharmacopeia (USP), the European Pharmacopoeia, WHO monographs, German Commission E monographs, or ESCOP monographs.
In ethnobotanical records, the preparation method involves grating the root and applying it as a poultice or taking it orally, but no quantitative dosage information is documented in the ethnobotanical sources. Specific dosage amounts, dosing intervals, and duration of use are not reported in any available sources for this species.
In broader PA-containing plant policy contexts, the German standard sets a maximum daily dose of 10 µg of PAs from herbal preparations. No corresponding species-specific dosage for C. grande has been established by any regulatory body.
The Boraginaceae, Asteraceae, and Fabaceae contain the most toxic PAs. To date, over 660 PAs, present as free-base PAs and PA N-oxides, have been identified in over 6,000 plant species, and about half of them are hepatotoxic.
Of particular importance regarding livestock and human toxicity are the Senecio, Crotalaria, Cynoglossum, Heliotropeum, Echium, and Symphytum species.
Numerous experiments and clinical observations have revealed that the toxicity of PAs often occurs in the liver. Exposure to large amounts can lead to acute poisoning, characterized by hepatic veno-occlusive disease (HVOD) or hepatic sinusoidal obstruction syndrome (SOS). Long-term ingestion of small amounts of PAs results in chronic toxicity, manifested as hepatic giant cell formation and hepatic fibrosis.
PAs exhibit developmental toxicity and have shown to be hepatotoxic, pneumotoxic, genotoxic, and carcinogenic.
Prolonged exposures may cause cell enlargement (megalocytosis), veno-occlusion in liver and lungs, fatty degeneration, nuclei enlargement with increasing nuclear chromatin, loss of metabolic function, inhibition of mitosis, proliferation of biliary tract epithelium, liver cirrhosis, nodular hyperplasia, and adenomas or carcinomas.
The earliest case of pyrrolizidine alkaloid-induced intoxication in a human was reported in 1920 and associated with the ingestion of PA-containing herbal tea. Since then, more than 8,000 pyrrolizidine alkaloid-poisoning cases have been documented in many countries, including Afghanistan, Britain, China, Germany, Hong Kong, India, Jamaica, South Africa, Switzerland, and the United States.
The first limits for PA-containing plants in pharmaceutical products were set in 1992 by the German Federal Ministry of Health, addressing herbal preparations from PA-producing plants. Herbs of the genera Symphytum, Borago, Brachyglottis, Cineraria, Alkanna, Tussilago, Lithospermum, Cynoglossum, Senecio, Eupatorium, Anchusa, Petasites, Heliotropium, and Erechthites were specifically identified as of concern.
The external use of PAs is considered safer than the oral or systemic administration, given that hepatic bioavailability should normally be minimal through topical application. However, this is a general principle derived from PA pharmacokinetics research and has not been specifically evaluated for C. grande preparations.
The plant contains pyrrolizidine alkaloids, which are generally hepatotoxic and considered unsafe for internal use; however, their topical safety and efficacy have not been well studied.
Pyrrolizidine alkaloids are found in various unrelated species of plants, particularly the families Compositae (Senecio spp.), Leguminosae (Crotalaria spp., Tephrosia spp.), and Boraginaceae (Heliotropium, Cynoglossum, Amsinckia, Echium, Trichodesma, and Symphytum spp.), and are produced as a defense mechanism against herbivorous pests, having been found to result in hepatotoxicity.
Cynoglossum grande is a non-invasive herbaceous perennial, distinguishing it from the related Old World species C. officinale, which has been designated a noxious weed in parts of North America.
The Boraginaceae family is widely recognized for its medicinal potential and diverse biological activities, including antioxidant, anti-inflammatory, antimicrobial, and hepatoprotective effects. Despite this promising profile, many species in this family remain poorly studied in terms of phytochemistry and pharmacology, providing valuable opportunities for drug discovery and natural product research.
There is currently no substantial scientific literature demonstrating wound healing or antimicrobial properties for C. grande or its extracts. While there is documentation of traditional use for wounds and sores, this use is not supported by modern scientific evidence, and caution is warranted due to the plant's potential toxicity.
The genus-level research on C. amabile illustrates the depth of study that would be required to properly characterize C. grande. There is currently no up-to-date review available on the traditional utilization, phytochemistry, pharmacology, toxicology, or clinical applications of closely related Cynoglossum species; this gap in knowledge restricts the safe use of such plants in clinical medication, quality assessment, and resource development.
In summary, Cynoglossum grande / Adelinia grandis remains essentially unstudied from a modern pharmacological perspective. Its traditional uses are confined to specific indigenous Californian cultures as documented in ethnobotanical databases, and no clinical, human, or rigorous in vitro or in vivo studies specific to this species exist in the published peer-reviewed literature. Given its membership in a genus known for hepatotoxic pyrrolizidine alkaloids, and the documented PA content of closely related species, the safety profile for internal use warrants significant caution on a precautionary basis.
Health conditions that Cynoglossum grande may help support.
Body systems that Cynoglossum grande may help support.
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