Shankhpushpi (Convolvulus pluricaulis Choisy)
1. Identity
Botanical and Taxonomic Classification
Convolvulus pluricaulis Choisy (synonym: Convolvulus prostratus Forssk.) belongs to the family Convolvulaceae and is a perennial herb native to the Indian subcontinent. According to the Ayurvedic Pharmacopoeia of India, Shankhpushpi consists of the whole plant of Convolvulus pluricaulis Choisy (also synonymized as Convolvulus microphyllus Sieb. ex Spreng.).
The Sanskrit name "Shankhpushpi" means "the plant with flowers shaped like a conch." The species stands out with small funnel-shaped flowers that range from white to light blue and slender stems that sprawl across sandy soils. The branches of C. pluricaulis are widely spread on the ground and can reach up to 30 cm in length.
Botanical Confusion and Adulteration
Plants other than C. pluricaulis — including Evolvulus alsinoides Linn. (Convolvulaceae), Clitoria ternatea Linn. (Papilionaceae), and Canscora decussata Schult. (Gentianaceae) — have also been used as Shankhpushpi by some practitioners. Because of the increasing demand for the drug, the genuine plant species has been over-exploited, and many unrelated plants are sold by crude drug dealers in India under the name "Shankhpushpi." Researchers have developed molecular (RAPD) and chemical (HPLC) markers to distinguish the authentic plant species from its adulterants.
Geographic Distribution
Convolvulus pluricaulis is a prostrate, spreading wild herb with a narrow distribution in India, found in the plains of Punjab, Uttar Pradesh, Haryana, Rajasthan, Bihar, and Chota Nagpur. The plant is also found in Burma.
Plant Parts Used and Common Preparations
The entire plant, including the roots, leaves, and stems, is utilized to make herbal treatments. The whole plant is used in Ayurvedic preparations, including its leaves, flowers, and roots, and is typically consumed in the form of powder, juice, decoction, or tablets, depending on the intended use. The various dosage forms — powder, paste, and syrup — are prepared using the whole plant or different parts of the plant as indicated in classical texts.
2. Traditional and Historical Use
Ayurveda
Shankhpushpi has a rich history of use in Ayurveda, dating back thousands of years. Ancient Ayurvedic texts, such as the Charaka Samhita and Sushruta Samhita, mention Shankhpushpi as a powerful "Medhya" (intellect-promoting) herb. The Charaka Samhita, an ancient foundational text of Ayurveda, described its use as paste (kalka) in the category of Medhya Rasayana. Shankhpushpi is known as a Medhya (brain tonic) Rasayana in the Indian traditional system, referring to a class of rejuvenating formulations said to enhance intellect and cognitive functioning.
In Ayurvedic formulations, the herb has been used for chronic cough, sleeplessness, epilepsy, hallucinations, and anxiety. In traditional Ayurveda, it is recommended as a brain tonic to promote intellect and memory, eliminate nervous disorders, and to treat hypertension; it has also been used as an antihelmintic, and for dysentery, as a hair tonic, for skin ailments, and to reduce high blood pressure. The leaves have specifically been recommended for depression and mental disturbance.
The Ayurvedic tradition has applied Shankhpushpi under a host of Sanskrit names, including Shyamakranta, Visnukranta, Vaishnava, Sankhaholi, Vishnugandhi, Vishnukranti, Shankavall, and others. Classical Ayurvedic properties attributed to the plant include Medhya (memory booster), Vamana, Deepana (enhances digestive fire), Pachana (helps in digestion), Rochana (stimulates appetite), Kusthahara (treats skin disease), Shothahara (reduces inflammation), and Hridaya (treats heart problems), among others.
Doshic Classification in Ayurveda
In Ayurvedic pharmacology, the herb is classified by its rasa (taste) as Tikta (bitter), its guna (qualities) as Snigdha (unctuous) and Picchila (sticky), and its vipaka as Madhura — meaning it undergoes sweet taste conversion after digestion. Early Ayurvedic texts link it to the Vata dosha, prescribing it for conditions of anxiety, insomnia, and poor memory.
Traditional Preparations
A powdered form of Shankhpushpi (churna) has been a common method of preparation in Ayurveda, easily digestible and traditionally mixed with liquids for consumption. Milk is also used in Ayurvedic tradition as a complementary substance to Shankhpushpi powder, serving as a nourishing base that aids the absorption of active compounds in the herb. As an important indigenous medicine, it has a long history of application for liver disease, epileptic disease, microbial disease, and central nervous system (CNS) disease in Ayurvedic medicine, traditional Chinese medicine, and other indigenous medical systems.
3. Key Chemical Constituents and Active Compounds
This medicinal herb has been reported to contain many bioactive phytoconstituents, including the alkaloid convolamine, the flavonoid kaempferol, and the phenolics scopoletin, β-sitosterol, and ceryl alcohol, which have been ascribed to the observed medicinal properties.
Broader classes of phytoconstituents identified in C. pluricaulis include Vitamin E, ascorbic acid, phthalic acid, squalene, decanoic acid, linoleic acid, tropane alkaloids, kaempferol, beta-sitosterol, pentanoic acid, and cinnamic acid.
Chemical studies of the whole plant have shown the presence of glycosides, coumarins, flavonoids and alkaloids, sitosterol glycoside, hydroxy cinnamic acid, octacosanol, tetracosane, and sucrose.
Specific alkaloids analyzed in the plant include convolidine, convolvine, and confoline, as well as other related tropane compounds.
Mechanisms of Action
Several active substances isolated from aerial sections of C. pluricaulis, including scopoletin, kaempferol, and β-sitosterol, have been demonstrated to act as GABAA agonists, which may help explain the antianxiety and CNS depressant properties of Shankhpushpi.
In network pharmacological analysis, key phytochemicals were found to interact with molecular targets including prostaglandin G/H synthase 1 and 2 (PTGS1 and PTGS2), endothelial nitric oxide synthase (NOS3), the insulin receptor (INSR), heme oxygenase 1 (HMOX1), acetylcholinesterase (ACHE), peroxisome proliferator-activated receptor-gamma (PPARG), and monoamine oxidase A and B (MAOA and MAOB), all of which are associated with neuronal growth, survival, and activity.
Notably, scopoletin showed the highest binding affinity with PTGS1, NOS3, PPARG, ACHE, MAOA, MAOB, and TRKB; quercetin with PTGS2; 4-hydroxycinnamic acid with INSR; and ayapanin with HMOX1. The findings indicate that these five compounds may account for the herb's memory-enhancement and neuroprotective effects.
Convolvulus pluricaulis has been reported to calm the nerves by regulating the synthesis of stress hormones, including cortisol and adrenaline, in the body.
The underlying mechanisms of the herb's effects on learning and memory in animal models may be attributed to antioxidant, neuroprotective, and cholinergic properties.
4. Scientific Evidence by Area of Use
4.1 Memory Enhancement and Cognitive Function
Animal/preclinical evidence (substantial): An aqueous and ethyl acetate extract of Convolvulus pluricaulis has been shown to increase memory functions and learning abilities in rodent models. A. racemosus and C. pluricaulis at the dose of 200 mg/kg (oral) showed significantly higher percent retention in memory tasks than piracetam, and multiple-treatment regimens also demonstrated significant dose-dependent increases in percent retention compared to control groups; the effect was more prominent with C. pluricaulis than with piracetam.
Pretreatment with C. pluricaulis for 7 days enhanced memory in aged mice, with significantly higher retention observed at 200 mg/kg compared to piracetam at 10 mg/kg. Hippocampal regions associated with learning and memory functions showed dose-dependent increases in acetylcholinesterase (AChE) activity in the CA3 area with C. pluricaulis treatment.
The ethanolic extract of Convolvulus pluricaulis and its aqueous and ethyl acetate fractions significantly improved memory retention and learning abilities in rats. A wide range of secondary metabolites including steroids, anthocyanins, flavonol glycosides, and triterpenoids have been isolated and are considered responsible for these memory-enhancing and nootropic properties.
Human/clinical evidence (limited): In an open-label clinical study of young healthy volunteers, a dose of 500 mg tablets of Shankhpushpi taken twice daily after food with milk was tested. Although preclinical studies suggest that Shankhpushpi has memory-enhancing, antioxidative, and anti-inflammatory effects, human data from well-controlled, rigorously designed clinical trials are currently lacking. Clinical studies of its polyherbal formulation have been conducted and are cited as providing justification for the ancient claim of its use as a brain tonic. Justification of its potential as an ancient brain tonic has been provided by clinical studies on a polyherbal formulation of this plant; however, these studies are generally of small scale, open-label, or lack rigorous controls, and no large randomized controlled trials have been published.
4.2 Anxiolytic and Anti-Stress Effects
Preclinical evidence (moderate): The crude herb and its metabolites have exhibited a wide range of in vitro and in vivo neuropharmacological effects, including anxiolytic, tranquilizing, anti-depressant, and anti-stress effects. The crude herb and its metabolites have exhibited in vitro and in vivo neuropharmacological effects, including memory enhancement, anxiolytic, tranquilizing, anti-depressant, anti-stress, neurodegenerative, anti-inflammatory, anti-oxidant, analgesic, sedative, anti-convulsant, and Alzheimer's disease-reversing effects.
Active substances isolated from the aerial sections of the plant act as GABAA agonists, which in preclinical pharmacology represents a plausible mechanism for reported sedative and anxiolytic activity.
Human evidence: There are no large RCTs for anxiety from Shankhpushpi. There are zero adequately powered, placebo-controlled, double-blind trials in humans with diagnosed anxiety disorders. The anxiolytic evidence currently rests entirely on preclinical (animal and in vitro) work.
4.3 Neuroprotection and Neurodegeneration
Convolvulus pluricaulis has long been used as a traditional nerve tonic in India. The neuroprotective effects of its aqueous extract have been studied against human microtubule-associated protein tau (hMAPτ)-induced neurotoxicity in an Alzheimer's disease Drosophila model. C. pluricaulis significantly offset hMAPτ-induced early death and extended lifespan, and diminished the level of tau protein in the tauopathy Drosophila model; it also enhanced antioxidant enzyme activities and ameliorated tau-induced oxidative stress.
Traditional knowledge and experimental evidence suggest that C. pluricaulis, alone or in combination, can enhance memory and protect against cognitive impairment; however, the underlying mechanisms supporting these claims remain largely unexplored.
Virtual ADME screening identified five active compounds from C. pluricaulis — scopoletin, 4-hydroxycinnamic acid, kaempferol, quercetin, and ayapanin — showing drug-likeness and blood-brain barrier permeability. Growing evidence suggests neurorestorative and memory-protective potentials for these compounds.
Human evidence: Based on a search of ClinicalTrials.gov (as of the time of review), no clinical trials testing Shankhpushpi were ongoing. The neuroprotection evidence therefore remains at the preclinical and computational stage. Human clinical trials in Alzheimer's disease or Parkinson's disease have not been conducted.
4.4 Antidepressant Activity
Isolated metabolites and crude extracts have exhibited a wide range of in vitro and in vivo pharmacological effects, including CNS depression, anxiolytic activity, tranquilizing, antidepressant, and antistress effects. Published preclinical research specifically investigating antidepressant-like activity used the mouse forced swim and tail suspension tests (Dhingra and Valecha, 2007, as cited in PMC3868798). This is exclusively animal-model evidence; no human clinical trials specifically for depression have been identified.
4.5 Anticonvulsant / Antiepileptic Activity
Convolvulus pluricaulis is a major ingredient in Ayurvedic formulae traditionally indicated for epilepsy. Experimental evidence suggests various neuroactive potentials, including antiepileptic properties. This evidence comes from preclinical studies. The interaction with phenytoin (see Section 6) demonstrates in vivo pharmacodynamic complexity at the antiepileptic level.
4.6 Hypolipidemic Activity
Significantly reduced serum cholesterol, LDL cholesterol, triglycerides, and phospholipids were found in cholesterol-fed gerbils treated with the ethanolic extract of the whole plant for 3 months. This evidence is animal-model based; no human lipid trials have been reported in the peer-reviewed literature reviewed here.
4.7 Antidiabetic Activity
Alam et al. reported that C. pluricaulis possesses antidiabetic activity; however, as with the hypolipidemic data, this finding derives from preclinical studies. Preclinical investigations have demonstrated antidiabetic activity among a broader spectrum of effects including nootropic, anxiolytic, antistress, antioxidant, hypolipidemic, and immunomodulatory properties. Clinical human evidence for antidiabetic use is absent from the peer-reviewed literature examined.
4.8 Thyroid Activity
Research has found that plant extract-induced inhibition in thyroid function is mediated through T4-to-T3 conversion. This is preclinical-only evidence. A small clinical study examined thyroid-stimulating properties in patients with simple diffuse goiter, as referenced in the phytochemical validation literature (Researchgate: Shankhapushpi validation study), but detailed clinical outcome data from this study were not accessible for full verification and should be treated cautiously.
4.9 Antioxidant Activity
An ethanolic extract of C. pluricaulis possesses significant antioxidant activity when tested in vitro. Shankhpushpi pretreatment in laboratory models also restored and regulated antioxidant markers (catalase, SOD) and apoptosis markers (p53 and caspase 3), and inhibited reactive oxygen species generation and depolarization of the mitochondrial membrane. All antioxidant evidence is in vitro or animal-based.
4.10 Amyloid Inhibition (In Vitro)
The syrup of Shankhpushpi strongly inhibited Aβ40 and methionine Aβ40 fibrillation in vitro compared to extracts of other herbs; however, this inhibition was affected by age and storage conditions, and after three months of storage, the inhibition efficiency was reduced or disappeared completely. This is purely in vitro data with significant practical limitations.
5. Body Systems and Health Areas
According to the ancient literature, this herb has been attributed with therapeutic properties including anxiolytic, neuroprotective, antioxidant, analgesic, immunomodulatory, antimicrobial, antidiabetic, and cardioprotective activities. Organizing by body system, the herb's research coverage spans the following areas:
- Central nervous system: CNS depression, anxiolytic, tranquillizing, antidepressant, antistress, neurodegenerative, antiamnesic, and anticatatonic activities have been demonstrated in preclinical studies.
- Cardiovascular system: Shankhpushpi has a mild blood pressure-lowering effect. Hypolipidemic activity has been demonstrated in animal models.
- Endocrine system: Preclinical evidence for antidiabetic and thyroid-modulatory effects (T4-to-T3 conversion inhibition) has been reported.
- Immune system: Immunomodulatory activity has been identified in preclinical investigations.
- Gastrointestinal system: Antiulcer and diuretic properties have been reported alongside the antioxidant and hypolipidemic findings.
- Antimicrobial: Antifungal and antibacterial activity have been demonstrated in in vitro and in vivo pharmacological studies.
6. Dosage Forms and Dosages Reported in Studies
One clinical study used a Shankhpushpi dose of 500 mg twice daily with milk. In an open-label clinical study of young healthy volunteers, a dose of 500 mg tablets taken twice daily after food with milk was the tested regimen.
In traditional Ayurvedic dosing references:
- Classical dosage guidance states: paste (kalka) 1–2 g; water decoction (Kashayam/infusion) 50–100 ml in divided doses per day; Kshara (alkali preparation) 250 mg–2 g in divided doses per day.
- In preclinical sedation studies, the plant showed a sedative effect at doses higher than 200 mg/kg in rodents, with a moderate-to-marked decrease in locomotor activity lasting 1–2 hours.
- In comparative memory studies, C. pluricaulis was used at 200 mg/kg orally in rodent models.
Shankhpushpi is commercially available in tablet/capsule form, powder, juice, oil, and decoction preparations.
7. Safety Considerations and Drug Interactions
Acute Toxicity
While generally considered safe in animal studies, with no toxicity observed up to 5,000 mg/kg in animal studies, formal long-term human safety data are not available. No acute toxicity was shown by C. pluricaulis up to high dose levels in animal models, as noted in the umbrella review.
Phenytoin Interaction (Clinically Documented)
During routine plasma drug level monitoring, an unexpected loss of seizure control and reduction in plasma phenytoin levels was noticed in two patients who were also taking the Ayurvedic Shankhpushpi preparation (SRC). A study was subsequently undertaken in rats to investigate the SRC–phenytoin interaction from both pharmacokinetic and pharmacodynamic aspects. Single-dose co-administration did not affect plasma phenytoin levels but significantly decreased the antiepileptic activity of phenytoin. On multiple-dose co-administration, SRC reduced not only the antiepileptic activity of phenytoin but also lowered plasma phenytoin levels. SRC itself showed significant antiepileptic activity compared to placebo and is considered worth further investigation.
Based on a review of herb–drug interactions, Shankhpushpi can decrease concentrations of the anti-seizure medication phenytoin, leading to decreased control of seizure. This is the most clinically significant and best-documented pharmacokinetic/pharmacodynamic interaction identified in the literature.
Blood Pressure
Shankhpushpi has a mild blood pressure-lowering effect, which is relevant for people suffering from low blood pressure or those already taking antihypertensive medications.
CNS Depressant Additive Effects
There is little published information on possible drug interactions with Convolvulus pluricaulis. Individuals on neurotransmitter-affecting drugs, such as antidepressants and antipsychotics, should exercise caution. Given the herb's documented GABAergic and CNS-depressant preclinical pharmacology, additive effects with other CNS depressants are a theoretical concern that has not been formally studied in humans.
Adulteration and Identity Risk
Because of increasing demand, this plant species has been over-exploited, and many unrelated plants are sold in the name of "Shankhpushpi" in Indian crude drug markets. This represents a distinct safety and efficacy consideration: products sold under the Shankhpushpi name may contain entirely different botanical species with different phytochemical profiles and unknown safety records.
Thyroid Caution
Research has identified that plant extracts can inhibit thyroid function via interference with T4-to-T3 conversion. The clinical significance of this effect in humans at typical supplement doses has not been formally established.
Overall Evidence Strength Summary
Little human research has been published in the Western medical literature regarding this plant. Preclinical (in vivo and in vitro) investigations have demonstrated a broad range of activities including nootropic, anxiolytic, tranquilizing, antidepressant, antistress, antioxidant, hypolipidemic, immunomodulatory, anti-inflammatory, analgesic, antimicrobial, antidiabetic, antiulcer, anticatatonic, and cardiovascular activity; clinical studies of polyherbal formulations have provided some justification for the ancient claim of the herb as a brain tonic, but these do not approach the evidentiary standard of large, double-blind, randomized controlled trials. Experimental evidence suggests various neuroactive potentials of C. pluricaulis, such as memory-enhancing, neuroprotective, and antiepileptic effects; however, precise mechanisms underlying the neuropharmacological effects remain unclear.
References
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