Convolvulus prostratus

Convolvulus prostratus (Shankhpushpi): A Comprehensive Reference

1. Identity and Botanical Classification

1.1 Accepted Name and Synonymy

Convolvulus prostratus Forssk. is a nootropic herb used in traditional medicinal systems, also frequently known by its taxonomic synonym Convolvulus pluricaulis Choisy. The species was formally published by Forsskål in 1775 (Fl. Aeg.-Arab. 203) and is classified within the kingdom Plantae, phylum Tracheophyta, class Magnoliopsida, order Solanales, family Convolvulaceae, genus Convolvulus.

Recognized synonyms include Convolvulus austroaegyptiacus Abdallah & Sa'ad, Convolvulus cancerianus Abdallah & Sa'ad, Convolvulus deserti Hochst. & Steud., Convolvulus evolvuloides Boiss., Convolvulus heterotrichus Maire, and Convolvulus microphyllus Sieber ex Spreng., among others. The name Convolvulus pluricaulis Choisy is the most widely used synonym in the pharmacological and Ayurvedic literature and is recognized as such by Plants of the World Online (Kew Science).

In English, the plant is commonly called Prostrate Bindweed. In the Indian medicinal system of Ayurveda, it is named Shankhpushpi. The name "Shankhpushpi" is derived from its characteristic conch-shaped flowers (Shankha meaning conch, and Pushpi meaning flower). Other vernacular and regional names recorded in various traditions include Sankhaphuli, Shankhini, Samkhapushpi, Sadaphuli, and Shankhapushpi.

1.2 Botanical Description and Habitat

Convolvulus prostratus is a perennial herb belonging to the Convolvulaceae family. It is a prostrate, spreading plant that resembles morning glory with conch-shaped flowers. The plant has linear-lanceolate leaves with short petioles and sharp tips, measuring 0.5 to 2 cm in length and 0.1 to 0.5 cm in width. The flowers are pink or white, appearing singly or in pairs, and are sessile or subsessile.

Convolvulus prostratus (Convolvulus pluricaulis) is an herb found in India and Burma. It belongs to the Convolvulaceae family and is ubiquitous in the north-western regions of India. The plant typically grows on sandy or rocky ground under xerophytic (dry) conditions in northern India.

1.3 Taxonomic Identity Controversy: The "Shankhpushpi" Problem

In Ayurveda, the preparation Shankhapushpi is, according to most sources, identical with Convolvulus prostratus, but some say Shankhapushpi is instead Clitoria ternatea. Some also say Shankhapushpi is Evolvulus alsinoides, which is another plant of the same family. The Ayurvedic Pharmacopoeia of India (API), the country's official regulatory reference for Ayurvedic plants, states Convolvulus pluricaulis is the authentic, gold-standard Shankhpushpi for cognitive development. This substitution issue is scientifically significant because these species are not the same plant and do not have identical chemical profiles.

1.4 Common Forms and Commercial Preparations

There are food-grade products of this herb, like powder and syrup, available in the market for use as a nutraceutical nootropic. Various pharmaceutical formulations are used for the treatment of neurodegenerative disease, stress, and gastric ulcers. In the cosmeceutical industry, it is used as a tonic for hair and skin-related ailments. The whole plant is the part most commonly used medicinally, and it is prepared in multiple forms including dried powder (churna), liquid extract (juice/swarasa), aqueous decoctions (kashayam), tablets, syrups, and as a component of polyherbal formulations. Commercial polyherbal products such as Remem (Zydus Industries, India), available in syrup and tablet forms, contain Convolvulus pluricaulis alongside species such as Centella asiatica, Celastrus paniculatus, Asparagus racemosus, and others.

2. Traditional and Historical Use

2.1 Ayurveda

C. prostratus occupies a remarkable position in the Indian system of medicine, particularly in Ayurveda, Siddha, and Unani traditions. Classified as a Medhya Rasayana—a rejuvenating drug for the brain and nervous system—it has been revered for centuries as an effective nervine tonic, memory enhancer, anxiolytic, and neuroprotective agent.

As per the ancient Indian medicinal scripture—the Charaka Samhita—this plant is superior to other nootropic drugs (Medhya rasayana) of Ayurveda. Ancient works of literature describe it as an ingredient of Medhya Rasayana, which is said to be life-promoting and to help heal various neurological ailments, strengthen the digestive system, improve skin and voice, and spark the intellect.

One of the revered ancient Indian medical practitioners, Acharya Charaka, used the white-flowered variety of C. prostratus (Shankhpushpi) along with the juice of Bacopa monnieri (Brahmi), Acorus calamus (Vacha), and Saussurea lappa (Kushtha) for alleviating insanity and epilepsy.

Ancient Ayurvedic texts frequently mention Shankhpushpi as a potent medhya rasayana—a rejuvenator for the mind. It has been used to improve memory, learning ability, and concentration, making it a cherished remedy for students and those seeking mental clarity. Historically, Convolvulus prostratus was often prepared as a syrup or decoction and administered to alleviate anxiety, stress, and insomnia. Its calming effects were used to soothe the nervous system, promoting restful sleep and overall mental well-being. Additionally, it was employed to manage epilepsy, hysteria, and other neurological disorders.

The plant figures in the Ayurveda, Siddha, and Unani systems of medicine. Convolvulus pluricaulis is also a major ingredient in Traditional Chinese formulae indicated for neurological conditions, namely dementia, anxiety, depression, insanity, and epilepsy.

In classical Ayurvedic pharmacology, the plant is described with specific taste and energetic properties: Rasa (taste) is Tikta (bitter); qualities (guna) are Snigdha (unctuous, oily) and Picchila (sticky); Vipaka is madhura (undergoes sweet taste conversion after digestion); Veerya is Sheeta (coolant in nature). Its special effect (Prabhava) is listed as Medhya—improving intelligence—and it balances Pitta and Kapha doshas.

2.2 Unani and Siddha Traditions

The plant is known as Shankhpushpi by Ayurvedic practitioners in ancient systems of Indian medicine, where it was regarded as a prominent memory-improving drug, a psychostimulant, and a tranquilliser in traditional Indian medicine. Its inclusion in the Unani system of medicine further extends its documented use across multiple classical Indian medical traditions.

3. Key Constituents and Active Compounds

3.1 Major Phytochemical Classes

The plethora of medicinal properties attributed to C. pluricaulis has been credited to its numerous phytoconstituents, which are primarily alkaloids, flavonoids, coumarins, and polyphenols. The plant is known to contain kaempferol, β-sitosterol, N-hexacosanol, taraxerol, taraxerone, delphinidine, and hydroxycinnamic acid as major phytoconstituents.

3.2 Alkaloids

The plant contains an alkaloid, namely Shankhpushpine (also written Shankhpuspine), which is known as a chemotaxonomic marker for this species. Other documented alkaloids include:

• Convolamine: reported to possess antihypoxic, immune-modulating, and anti-inflammatory activity.
• Convoline: reported to show anti-epileptic activity.
• Convolvine: reported to exhibit antihypoxic, immune-modulating, and anti-inflammatory activity; blocks muscarinic (M) receptors; and exhibits nootropic, cytotoxic, and sedative activity.

3.3 Flavonoids

CP has been endowed with several potential phytochemicals, namely flavonoids (kaempferol and quercetin), coumarins (scopoletin and ayapanin), phenolic acid (hydroxycinnamic acid), and phytosterol (β-sitosterol) that are related to its pharmacological effects.

3.4 Carbohydrates and Other Constituents

Research has indicated that the plant contains carbohydrates (D-glucose, maltose, rhamnose, sucrose, starch), proteins, and amino acids, in addition to alkaloids. It also contains volatile oil, fatty alcohols, and hydroxycinnamic acid, which endow the plant with nootropic capabilities.

3.5 Anthocyanins

Delphinidine, an anthocyanin, has been identified and is reported to have antioxidant, anti-mutagenic, anti-inflammatory, and antiangiogenic properties.

4. Established and Proposed Mechanisms of Action

4.1 Cholinergic Modulation

The alkaloid convolvine present in the herb has been found to block cholinergic muscarinic receptors M2 and M4. Convolvine also aids in potentiating the effect of the muscarinic memory enhancer arecoline, thereby imparting nootropic abilities to the plant. The herb is proposed to enhance cholinergic neurotransmission, which is vital for learning and memory. The alkaloids shankhpushpine and convolvine have been described as inhibiting the enzyme acetylcholinesterase (AChE).

4.2 Antioxidant and Anti-inflammatory Properties

These phytoconstituents have well-described antioxidant and anti-inflammatory properties, which aids in protecting neuronal cells against oxidative stress. Additionally, natural compounds such as flavonoids aid in modulating neuronal cell signaling pathways.

4.3 Stress Hormone Modulation

Convolvulus pluricaulis has been reported to calm the nerves by regulating the stress hormone synthesis (cortisol and adrenaline) in the body.

4.4 Synaptic Plasticity

In healthy rats, CP extract has been shown to promote memory capacity by modulating synaptic plasticity in the hippocampus.

4.5 Acetylcholinesterase Activity in Hippocampal Regions

Administration of Convolvulus pluricaulis has been found to increase acetylcholinesterase activity in the hippocampal CA1 and CA3 regions associated with memory function and learning abilities.

5. Scientific Evidence by Area of Use

5.1 Cognitive Enhancement / Nootropic Effects

Preclinical evidence (animal studies): The largest body of evidence for C. prostratus comes from in vitro and in vivo animal studies.

An aqueous and ethyl acetate extract of Convolvulus pluricaulis has been shown to increase memory functions and learning abilities in animal studies. The ethanolic extract of Convolvulus pluricaulis and its aqueous and ethyl acetate fractions significantly improved memory retention and learning abilities in rats.

One study aimed to investigate the neuroprotective effect of Convolvulus pluricaulis aqueous extract (AE) against scopolamine (1 mg/kg body weight)-induced neurotoxicity in the cerebral cortex of male Wistar rats. The study investigated cognitive-enhancing properties of AE using Elevated Plus Maze (transfer latency) and Morris Water Maze tests. Pretreatment of rats with AE at 150 mg/kg body weight significantly reduced scopolamine-induced increase in transfer latency in EPM, and in the Morris Water Maze, administration of extract improved the impairment of spatial memory induced by scopolamine.

In studies comparing C. pluricaulis and Asparagus racemosus, both at the dose of 200 mg/kg (per oral) showed significantly higher percent retentions than piracetam. Multiple treatments for three days also demonstrated significant dose-dependent increases in percent retention compared to control group, with the effect more prominent with C. pluricaulis than piracetam. Pretreatment with C. pluricaulis for 7 days enhanced memory in aged mice, as significantly higher retention was observed with C. pluricaulis at 200 mg/kg (per oral) compared with piracetam at 10 mg/kg (per oral).

In a rat model of neurotoxicity induced by aluminum injection, daily administration of shankhpushpi aqueous extract at 150 mg/kg for 3 months decreased the elevated enzymatic activity of acetylcholinesterase and also inhibited the decline in Na⁺/K⁺ ATPase activity.

In another study, Rawat and Kothiyal found that aquo-methanolic, ethanolic, and petroleum ether extracts isolated from CP at doses of 50–400 mg/kg exhibited anxiolytic, memory-enhancing, and nootropic activity as evaluated by using the Elevated Plus Maze (EPM) and step-down models in mice.

When different shankhpushpi plants were compared, the Convolvulus pluricaulis extract showed maximum nootropic and anxiolytic activity at 100 mg/kg dose, whereas Evolvulus alsinoides extract and Clitoria ternatea extract showed maximum memory-enhancing and anxiolytic activity at 200 and 100 mg/kg doses, respectively.

Human/clinical evidence: 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. A few open-label clinical trials have been carried out, but no randomized controlled clinical trials have tested whether shankhpushpi improves cognitive function or prevents age-related cognitive decline.

Clinical studies of its polyherbal formulations have been carried out and have been cited as justifying its ancient claim as a brain tonic. However, since these trials were conducted with multi-ingredient formulations—not isolated C. prostratus—the contribution of the individual plant cannot be independently assessed from these data.

Despite its elaborative preclinical pharmacological profile, detailed clinical investigations and mechanistic mode-of-action studies of this important herb are yet to be executed.

Evidence strength: Preliminary. Predominantly preclinical (rodent); human clinical trial evidence is absent or very limited and confined to open-label polyherbal studies.

5.2 Anxiolytic and Antidepressant Effects

Preclinical evidence: The crude herb and its metabolites have exhibited a wide range of in vitro and in vivo neuropharmacological effects, including memory enhancement, anxiolytic, tranquilizing, anti-depressant, anti-stress, and anti-inflammatory effects.

This herb has been shown in preclinical studies to exhibit anti-convulsant, anti-depressant, anxiolytic, sedative, anti-inflammatory, anti-oxidant, analgesic, nootropic, spasmolytic, and neuroprotective activities.

All three commonly used Shankhpushpi plants (Convolvulus pluricaulis, Evolvulus alsinoides, and Clitoria ternatea) showed central nervous system depressant action at higher dose levels in animal studies.

Evidence strength: Preliminary; animal and in vitro data only. No controlled human clinical trials evaluating anxiolytic or antidepressant endpoints have been conducted on this species alone.

5.3 Neuroprotection and Neurodegenerative Disease

Preclinical experimental evidence suggests various neuroactive potentials of CP, including memory-enhancing, neuroprotective, and antiepileptic effects, though precise mechanisms underlying these neuropharmacological effects remain unclear.

Previous research has demonstrated beneficial effects of extracts of this plant in in vitro and in vivo models of Alzheimer's disease (AD). Computational approaches have aimed at deciphering the molecular basis of neuroprotective effects of CP phytochemicals against the pathology of dementia disorders such as Alzheimer's and Parkinson's disease.

Evidence strength: Preliminary. Evidence is limited to animal/in vitro studies and computational modeling. No human clinical trials specifically targeting neurodegenerative outcomes have been published.

5.4 Anticonvulsant Effects

The plant has been studied for use as an anticonvulsant with mixed results. The alkaloid convoline has been reported to have anti-epileptic activity in preclinical studies.

Evidence strength: Preliminary and mixed; animal data only. Human data are absent.

5.5 Hypolipidemic Effects

In cholesterol-fed gerbils, shankapushpi was observed to have significantly helped reduce serum cholesterol, low-density lipoprotein cholesterol, and triglycerides after ninety days.

Evidence strength: Very preliminary; animal study only; no human data available.

5.6 Thyroid Modulation

Shankhpushpi demonstrated a thyroid-suppressing effect when administered at 0.4 mg/kg to mice with hyperthyroidism.

Evidence strength: Very preliminary; single animal study only; no human data available. This finding has safety implications for individuals with thyroid conditions.

5.7 Antidiabetic Activity

It has been used for improving memory and cognitive function, reducing stress and anxiety, and to treat conditions such as insomnia and diabetes. Preclinical investigations have demonstrated antidiabetic activity among other effects.

Evidence strength: Very preliminary; preclinical only; no controlled human trials for glycemic outcomes.

5.8 Antimicrobial, Antifungal, and Other Activities

Preclinical investigations have also shown antimicrobial, insecticidal, antifungal, antibacterial, anthelmintic, antiulcer, and anticatatonic activity.

Evidence strength: Very preliminary; in vitro or animal data only.

6. Body Systems and Health Areas of Association

• Central Nervous System: C. pluricaulis has been indicated for various human ailments affecting the CNS, namely anxiety, depression, epilepsy, and dementia.
• Cardiovascular System: In classical Ayurvedic use, it is described as a cardiac tonic and indicated in bleeding disorders and hypertension.
• Endocrine System: Preclinical data indicate possible thyroid-suppressing effects and antidiabetic activity.
• Lipid Metabolism: Animal data suggest a hypolipidemic action on serum cholesterol, LDL, and triglycerides.
• Immune System: Pharmacological attributes include anti-inflammatory, antioxidant, and immunomodulatory properties.
• Digestive System: It is described in Ayurveda as carminative because of its bitter taste, and it has anulomana action (facilitating movement of doshas in the proper direction) due to its unctuousness.
• Respiratory System: Classically indicated in vata-pittaja kasa (a type of cough) and in hoarseness of voice.
• Urinary System: Classically described as increasing urine production and used in conditions like painful micturition and urinary tract infection.

7. Dosage Forms and Reported Dosages

The following dosages are those reported in traditional Ayurvedic sources and studies reviewed in the literature. Experimental (animal) dosages are noted separately.

7.1 Traditional / Ayurvedic Dosages

Traditional Ayurvedic dosage forms and quantities include: paste 1–2 g; water decoction (kashayam/infusion) 50–100 ml in divided quantity per day; and kshara (alkali preparation) 250 mg–2 g in divided dose per day.

7.2 Dosages Used in Preclinical (Animal) Studies

• Aqueous extract at 150 mg/kg body weight (Wistar rats) used in scopolamine-induced cognitive impairment studies.
• 200 mg/kg per oral was the dose showing significantly higher percent retention than piracetam in rodent studies.
• Doses of 50–400 mg/kg of various solvent extracts were used to evaluate anxiolytic, memory-enhancing, and nootropic activity.
• In comparison studies among three Shankhpushpi species, Convolvulus pluricaulis extract showed maximum nootropic and anxiolytic activity at 100 mg/kg.
• Experiments in rats with two different doses—100 and 200 mg/kg—showed the drug significantly improved memory and learning.
• Thyroid-suppressing effects were observed at 0.4 mg/kg in a mouse model.

7.3 Acute Toxicity Threshold (Animal)

No acute toxicity was shown by C. pluricaulis up to a dose of 5000 mg/kg in albino Wistar rats. The whole extract of C. pluricaulis, when assessed for toxicology, generates an LD₅₀ of approximately 1250 mg/kg (range 1000–1500 mg/kg).

8. Safety Considerations and Drug Interactions

8.1 General Safety Profile

Shankhpushpi is generally considered safe when used according to recommendations, though it may lower blood pressure and interact with some medications. Little human research has been published in the Western medical literature regarding this plant.

8.2 Blood Pressure

Shankhpushpi has a mild blood pressure-lowering effect, and individuals suffering from low blood pressure or those taking anti-hypertensive medications should be aware of this before use.

8.3 Phenytoin Drug Interaction — Documented and Clinically Significant

Based on a documented review of herb-drug interactions, the Ayurvedic syrup shankhpushpi can decrease concentrations of phenytoin, an anti-seizure medication, leading to decreased control of seizure. In two patients with seizure who were also taking shankhpushpi, there was an unexpected loss of seizure control and reduction in plasma phenytoin levels.

In a study in rats, a single dose of shankhpushpi and phenytoin co-administration did not affect plasma phenytoin levels, but decreased the antiepileptic activity of phenytoin significantly. On multiple-dose co-administration, shankhpushpi reduced not only the antiepileptic activity of phenytoin but also lowered plasma phenytoin levels.

A preclinical study in rats showed that administration of a single dose of C. pluricaulis and phenytoin (oral/i.p.) decreased the antiepileptic activity of phenytoin significantly, and multiple-dose administration reduced the antiepileptic activity of phenytoin along with lowering of phenytoin levels in plasma.

This phenytoin interaction has been confirmed in at least two human case reports and in preclinical rat studies, and is the most clinically significant documented interaction for this herb. Individuals taking phenytoin for epilepsy should be aware of this interaction.

8.4 Sedative Potential at Higher Doses

All three plants studied as Shankhpushpi showed central nervous system depressant action at higher dose levels in animal studies. This CNS-depressant activity could theoretically compound the effects of sedative drugs or alcohol, though this has not been formally studied in humans.

8.5 Thyroid Considerations

Shankhpushpi demonstrated a thyroid-suppressing effect when administered to mice with hyperthyroidism. This preclinical finding suggests that individuals with pre-existing thyroid disorders or those taking thyroid medications should be aware of this potential effect, though no human data are available to confirm clinical relevance.

8.6 Botanical Adulteration and Identity Risk

Across India, four different plant species are all sold under the Shankhpushpi label. All of them have some cognitive or nervine properties and have been used in traditional Ayurvedic practice in different regions. But they are not the same plant and do not have identical chemical profiles. This means the safety profile and pharmacological activity of products labeled "Shankhpushpi" may vary considerably depending on the actual species present.

9. Limitations of the Current Evidence Base

Despite an elaborative preclinical pharmacological profile, detailed clinical investigations and mechanistic mode-of-action studies of this herb are yet to be executed. 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.

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. Most clinical trials that do exist have been conducted using polyherbal formulations rather than C. prostratus as a single, isolated agent, and many lack the rigorous design (randomization, blinding, adequate controls, and standardized extract characterization) necessary to draw firm conclusions.

Furthermore, the long-standing taxonomic confusion around the Shankhpushpi name—with at least four distinct species sold under this designation—introduces significant uncertainty into the interpretation of the existing literature, as studies may not always have used botanically verified material.

References

• Balkrishna A, Thakur P, Varshney A. Phytochemical Profile, Pharmacological Attributes and Medicinal Properties of Convolvulus prostratus – A Cognitive Enhancer Herb for the Management of Neurodegenerative Etiologies. Frontiers in Pharmacology. 2020;11:171. PMC/PubMed.
• Hannan MA, et al. Protective Mechanisms of Nootropic Herb Shankhpushpi (Convolvulus pluricaulis) against Dementia: Network Pharmacology and Computational Approach. Evidence-Based Complementary and Alternative Medicine. 2022. PMC/PubMed.
• Role of Shankhpushpi (Convolvulus pluricaulis) in neurological disorders: An umbrella review covering evidence from ethnopharmacology to clinical studies. Neuroscience & Biobehavioral Reviews. ScienceDirect. 2022.
• Sharma K, et al. Effect of Convolvulus pluricaulis Choisy and Asparagus racemosus Willd on learning and memory in young and old mice: a comparative evaluation. PubMed. 2010.
• In vivo investigation of the neuroprotective property of Convolvulus pluricaulis in scopolamine-induced cognitive impairments in Wistar rats. PubMed. 2011.
• Alzheimer's Drug Discovery Foundation (ADDF). Cognitive Vitality: Shankhpushpi & Your Brain.
• ADDF Cognitive Vitality Report: Shankhpushpi – Full Researchers' PDF.
• Plants of the World Online (Kew Science). Convolvulus prostratus Forssk. – Accepted name and synonymy.
• GBIF Backbone Taxonomy. Convolvulus prostratus Forssk. Species record and synonyms.
• Plant Science Today. Convolvulus prostratus Forssk.: A Memory Boosting Herb. 2023.
• Effects of medicinal plants on Alzheimer's disease and memory deficits. PMC. 2017.
• International Journal of Pharmaceutical Sciences and Drug Research. Convolvulus pluricaulis as a Cognition Booster: Relevance to Alzheimer's Disease.
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• IJPS Journal. Shankhpushpi (Convolvulus prostratus): Natural Brain Booster and Nootropic Herb. 2026.