Quisqualis

Quisqualis (Combretum indicum): A Comprehensive Reference

1. Identity, Nomenclature, and Botanical Description

1.1 Scientific Names and Taxonomic Status

The accepted scientific name of the plant commonly called Quisqualis is Combretum indicum (Linnaeus) DeFilipps, with Quisqualis indica Linnaeus serving as a widely used synonym. The name Quisqualis indica Linnaeus was the generitype for the genus Quisqualis Linnaeus and was monotypic at the time of publication in 1762; the accepted name was formally revised to Combretum indicum (Linnaeus) DeFilipps. The genus epithet has historical significance: the term "Quisqualis," which pertains to stems and plant parts of different colors, comes from the Malay word Udani. The term "indica" means Indian.

The plant is classified in the order Myrtales, family Combretaceae, genus Combretum, with the Genbank common name "Rangoon creeper." Combretum indicum belongs to the family Combretaceae, a family comprised of more than twenty genera and six hundred species.

1.2 Common Names

The plant is known under numerous vernacular names across regions. These include: Dawe-hmaing-nwe (Myanmar), Udani (Malaysia), Shi jun zi (Chinese), Dok ung (Laos), Quiscual (Spanish), Shikunshi (Japanese), Cha mang (Thailand), Daay giun (Vietnamese), and Niog-niogan (Philippines). In Hindi it is Rangoon ki bel; in Bengali, Madhumanjari; in Marathi, Madhumati; and in Tamil, Irangunmalle. English common names include Rangoon creeper, Burma creeper, Chinese honeysuckle, and drunken sailor.

1.3 Botanical Description and Geographic Distribution

Combretum indicum, commonly known as the Rangoon creeper or Burma creeper, is a vine with red flower clusters that is native to tropical Asia, growing in thickets, primary and secondary forest, and along river banks in the Indian subcontinent, Malaysia, and the Philippines. The Rangoon creeper is a vigorously climbing ligneous vine that can reach from 2.5 meters to up to 8 meters.

The leaf blade is mostly oblong-elliptic or elliptic, 5–18 × 2.5–7 cm. Flowers are fragrant. The calyx tube is 5–9 cm; petals open white, later turning yellowish on the outside and reddish on the inside. The 30 to 35 mm long fruit is dark brown, ellipsoidal and has five stiff and prominent wings; the seed tastes like almond or coconut when mature.

The plant is found throughout Western Asia, the Himalayas, India, Bangladesh, Sri Lanka, Indochina, Malesia, China (including Taiwan), eastern Africa, New Guinea, and Australia. A vigorous, fast-growing, climbing, woody shrub reaching a length of 2–8 m, it is native to Asia and possibly tropical Africa. It has been widely cultivated as an ornamental for its aromatic flowers, as a hedge climber, and for use in traditional medicine, resulting in the species' widespread distribution to all tropical regions of the world.

1.4 Common Preparations and Dosage Forms

All major parts of the plant—seeds, fruits, leaves, roots, flowers, and stem bark—have been employed medicinally. The plant is widely used in traditional medicine, valued particularly for ridding the body of parasites, and all parts of the plant are used. Preparations documented in the ethnobotanical and pharmacological literature include:

• Seed/Fruit decoctions: In Indonesia, a decoction of the fruit is drunk to expel intestinal worms.
• Roasted seeds: In China, ripe seeds are roasted and given in diarrhea and fever.
• Macerated oil: The seeds, macerated in oil, are applied to parasitic skin diseases, boils, or sores on children's faces.
• Leaf juice: The juice expressed from the leaves is used to heal boils and ulcers, and to treat ringworm infection and fever.
• Standardized ethanol extracts: Modern research employs standardized ethanol extracts of the seeds or leaves, characterized by quisqualic acid content and other markers.
• Fruit gargle: A concentrated decoction of the fruit is used as a gargle that is effective against toothache.

2. Traditional and Historical Use

2.1 Traditional Chinese Medicine

Shijunzi (使君子), or Fructus Quisqualis, is the dry fruit of Quisqualis indica L. (Combretaceae) collected in the fall. This herbal medicine is officially listed in the Chinese Pharmacopoeia and is used mainly as an anthelmintic. As early as 1861, Dr. John Ivor Murray sent a sample of the "nuts" to the Museum of Economic Botany in Edinburgh, with a note that they were "used by the Chinese for worms" and a description of the means of preparation and dosage. In Chinese medical practice, the herb is described with multiple functional categories: it is regarded as antiparasitic against roundworms, pinworms, and tapeworms; it harmonizes and tonifies the spleen and stomach; and it is used for childhood nutritional impairment, abdominal distension, and loss of appetite.

2.2 Southeast Asian Traditional Medicine

In Thai traditional medicine, the seeds contain oil and quisqualic acid that act as anthelmintics, and the flowers are used against diarrhea and eaten as vegetable. In Malaysia, the fruits are eaten to expel intestinal worms, and a decoction of the fruit is given to children to stop diarrhea. The fruits and seeds are used as a vermifuge and for rickets in the Philippines, Thailand, and the Indochina region. The roots are used to relieve cough and hiccups; in the Philippines, the plant is used to treat diseases of the chest. In Vietnam, the fruit is used to expel intestinal worms and the roots are used to soothe rheumatism and assuage gastric discomfort.

2.3 South Asian (Ayurvedic and Folk) Traditions

Some of its leaves, flowers, fruits, and roots have been used for the treatment of fever, rheumatism, nephritis, skin diseases, migraine, and dysuria. In Bangladesh, the seeds are used for diarrhea, fever, boils, ulcers, and helminthiasis. Quisqualis indica L. of the Combretaceae family is a traditional medicine that is widely used for various gastrointestinal discomfort including stomach pain, constipation, and digestive problems.

2.4 Additional Regional Uses

Phytochemicals isolated from various plant parts or combined with other substances are used to treat a variety of conditions including rickettsial infections, urinary tract infections, body aches, toothaches, stomach pains, colds, and gastric disorders. The plant is widely used in traditional medicine, valued particularly for ridding the body of parasites. In Indonesia, the flowers are used in salads to add color.

3. Key Constituents and Active Compounds

3.1 Overview of Phytochemical Classes

The study of phytochemicals in Combretum indicum has gained attention over the past few decades. This plant has diverse traditional usages due to a wide range of phytoconstituents found in it, such as steroids, alkaloids like carbamate, terpenoids, saponins, carbohydrates, proteins, amino acids, and quinone. A comprehensive survey of the literature identifies the following compound classes and specific molecules across different plant parts:

• Alkaloids / neuroactive amino acids: Rutin, pelargonidin-3-glucoside, quisqualic acid, and mannitol are among the many phytochemicals that Combretum indicum possesses.
• Amino acids: Various amino acids including arginine, aspartic acid, proline, and histidine are also present in the plant.
• Leaf-specific compounds: Phytochemical screening of the leaf extract revealed rutin, arjunolic acid, oleanolic acid, trigonelline, vitexin, orientin, iso-orientin, and several monosaccharides including D-glucose and D-fructose.
• Flower-specific compounds: The flowers of Combretum indicum are composed of numerous phytochemicals including linalool oxides, quercetin, gallic acid, and pelargonidin-3-glucoside.
• Seed-specific compounds: The seeds are rich in a fixed oil comprising linoleic, oleic, palmitic, stearic, and arachidic acids, along with a sterol, an alkaloid possessing anthelmintic properties, and the neuroexcitatory amino acid quisqualic acid.

3.2 Quisqualic Acid: The Signature Compound

The most pharmacologically distinctive and studied constituent is quisqualic acid. The neuroexcitatory L-quisqualic acid was first isolated from the seeds of Quisqualis indica and functions as an agonist at the quisqualate excitatory amino acid receptor in the mammalian central nervous system. The seeds contain quisqualic acid, which is an agonist for the AMPA receptor, a kind of glutamate receptor in the brain. This chemical is linked to excitotoxicity (cell death).

Quisqualic acid is an excitatory amino acid, like N-methyl-D-aspartic acid and kainic acid, and the receptor of this alkaloid is sometimes called the quisqualate receptor. Quisqualic acid has shown excitatory effects on cultured neurons as well as in a variety of animal models; it causes various types of limbic seizures and neuronal damage at higher doses.

As an active component with anthelmintic activity, quisqualic acid was isolated and its chemical structure determined. The alkaloid was previously isolated from the fruit of Quisqualis chinensis and Q. indica, and its anthelmintic activity reported. Quisqualic acid exhibits marked anthelmintic activities. This active principle somewhat resembles the actions of the anthelmintic α-santonin. In China, seeds of Combretum indicum are used as a substitute for α-santonin as a drug.

3.3 Other Notable Constituents

The Q. indica extract contains various phytoconstituents such as tannins, trigonelline, L-proline, L-asparagine, quisqualic acid, rutin, and cysteine synthase that are responsible for its various pharmacological activities. Four diphenylpropanoids can be isolated from the stem bark, and the presence of linoleic, oleic, palmitic, and stearic acids is also reported. In a screening activity for active anticancer compounds derived from traditional Chinese medicine, studies reported that 25-O-acetyl-23,24-dihydro-cucurbitacin F from C. indicum showed significant cytotoxic activity.

4. Established and Proposed Mechanisms of Action

4.1 Anthelmintic Mechanism

In natural medicine tradition, Quisqualis indica has an anthelmintic effect and is used to treat roundworm infection. Quisqualic acid resembles the action of the anthelmintic α-santonin, and in some countries the seeds of the plant are used to substitute for the drug. The seeds have been used for treating roundworm and pinworm infections; quisqualic acid is toxic to the parasite and kills it in the digestive tract. Quisqualic acid is an amino acid obtained from the seeds of C. indicum. Studies on the neuromuscular junction of crayfish found that quisqualic acid could induce desensitization of the receptor to L-glutamic acid — a mechanism by which the compound paralyzes invertebrate parasites.

4.2 Antioxidant Mechanism

Combretum indicum, known as Rangoon creeper or Chinese honeysuckle, is an abundant source of phenols and flavonoids that have a crucial role in free radical scavenging. The high polyphenol and flavonoid content, including rutin, quercetin, and gallic acid, underlies direct free-radical-scavenging activity as measured in DPPH and reducing power assays.

4.3 Anti-inflammatory Mechanism

A flower extract showed significant and dose-dependent activity in acute and chronic anti-inflammatory models in Wistar rats. The phytochemicals of Combretum indicum show anti-inflammatory, antipyretic, and immunomodulatory activity.

4.4 Acetylcholinesterase Inhibition

In the search for new acetylcholinesterase inhibitors from plant origin, it was demonstrated that the methanolic extract of Q. indica flower exhibited this activity. The extract inhibited electric eel acetylcholinesterase in a dose-dependent manner with an IC50 value of 0.77 µg/ml. The Michaelis-Menten constant (Km) for the hydrolysis of acetylthiocholine iodide was 0.034 mM. A methanolic flower extract also inhibited acetylcholinesterase in vitro. These findings are strictly in-vitro and have not been evaluated in human studies.

4.5 Antidiabetic Mechanism

Pathway analysis reveals that active constituents are associated with insulin secretion and pancreatic secretion, indicating that CILEx (leaf extract) is a potential antidiabetic agent whose antidiabetic and lipid-lowering activities appear to operate through potentially regulating insulin secretion, pancreatic secretion, and lipolysis regulation in adipocytes.

5. Scientific Evidence by Area of Use

5.1 Anthelmintic / Antiparasitic Activity

Evidence strength: Preclinical (in vitro and animal); historical pharmacopoeial listing; no rigorous modern randomized clinical trials identified.

The anthelmintic application is the best-documented medicinal use. Shijunzi, the dry fruit of Quisqualis indica, is officially listed in the Chinese Pharmacopoeia and is used mainly as an anthelmintic. Early in-vitro work investigated quisqualic acid's effects on the nematode Ascaris suum: Ishizaki et al. (1973) examined the effect of quisqualic acid upon Ascaris suum in vitro in comparison with those of kainic acid, α-allokainic acid, and pyrantel pamoate. The prospects for Combretum indicum seeds as an anthelmintic are limited, however, due to the toxic side-effects of quisqualic acid. No controlled human clinical trials on anthelmintic efficacy have been identified in peer-reviewed literature as of the available search results.

5.2 Antidiabetic and Antidyslipidemic Activity

Evidence strength: Preclinical animal studies only; no human clinical data identified.

One PMC-indexed study investigated UPLC-QTOF/ESI-MS-based phytochemical profiling of Combretum indicum leaf extract (CILEx) and explored its in vitro antioxidant and in vivo antidiabetic effects in a Long–Evans rat model; after a one-week intervention, blood glucose, lipid profile, and pancreatic architecture were evaluated. Results showed a very promising antioxidative effect of CILEx. Both doses of CILEx were found to significantly (p < 0.05) reduce blood glucose, LDL, and total cholesterol (TC), and increase HDL. Pancreatic tissue architectures were much improved compared to the diabetic control group. These findings are restricted to a streptozotocin- or alloxan-induced rodent model and cannot be extrapolated directly to human efficacy.

5.3 Antioxidant Activity

Evidence strength: In vitro and animal studies; no controlled human trials identified.

A study selected Combretum indicum leaf to investigate its antioxidant and antimicrobial potential. The leaf extract was prepared with methanol solvent. Antioxidant potentiality was assessed by free radical scavenging assay with DPPH using ascorbic acid as standard. Antimicrobial activity was investigated by disc diffusion. Results showed that the plant extract exhibits a dose-dependent scavenging of DPPH with an IC50 of 48.87 µg/ml, while the standard ascorbic acid showed an IC50 value of 21.14 µg/ml. The flower extract gave high total polyphenol contents and showed strong antioxidant activity. All antioxidant evidence is currently in vitro.

5.4 Antimicrobial Activity

Evidence strength: In vitro only; traditional claims not confirmed in controlled trials.

Detailed GC-MS analysis of methanolic and chloroform extracts of Combretum indicum evaluated phytochemical profiles, revealing a diverse range of bioactive compounds. Major constituents identified include alkaloids, terpenoids, and flavonoids, and the findings highlight the presence of metabolites having antioxidant, antimicrobial, and anti-inflammatory potentials. However, as it shows low antifungal and antibacterial activity in vitro, its traditional use to stop infections has not been confirmed.

5.5 Anti-inflammatory and Antipyretic Activity

Evidence strength: Animal models and in vitro; no human clinical trials identified.

Various pharmacological studies have shown that the plant possesses multiple bioactivities such as immunomodulatory, anti-diabetic, anti-inflammatory, antioxidant, antibacterial, anthelmintic, analgesic, anti-dyslipidemia, and anti-asthmatic activities. Anti-inflammatory activity has been assessed in rodent models using flower extracts. Evidence is restricted to animal and cell-based studies; no human trials have been reported.

5.6 Anticancer / Cytotoxic Activity

Evidence strength: In vitro screening only; no clinical evidence.

In a test for active anticancer compounds, 25-O-acetyl-23,24-dihydro-cucurbitacin F showed significant cytotoxicity activity in vitro. One study reported the antiproliferative effect of Q. indica volatile oils on lung cancer cell line A549, finding that upregulation of p53 induces apoptosis, with the p53-mediated mitochondrial apoptosis pathway stimulating caspase-8 activity, which in turn releases apoptogenic factors such as cytochrome-C. Although many studies have examined the importance of plant extracts as anticancer agents, these studies need further investigation, including cytotoxicity and safety assessments in other cancer cell types. No human clinical data exist.

5.7 Gastrointestinal Activity

Evidence strength: Traditional use well-documented; limited preclinical study.

Quisqualis indica L. of the Combretaceae family is a traditional medicine widely used for various gastrointestinal discomfort including stomach pain, constipation, and digestive problems. A decoction of the seed is used as a vermifuge and is given to children to stop diarrhea. One peer-reviewed study investigated the effect of ethanolic flower extract of Q. indica on experimental esophagitis in albino Wistar rats, examining whether the extract's phenol and flavonoid content could exert protective effects via free radical scavenging. This work, indexed on PubMed (PMID 30184413), is in the animal model stage with no human data available.

5.8 Acetylcholinesterase Inhibition (Neuroprotective Potential)

Evidence strength: In vitro only; no in vivo or clinical evidence.

The finding that methanolic flower extract inhibited acetylcholinesterase with an IC50 of 0.77 µg/ml in vitro is of potential interest for cognitive health research, but this activity was only demonstrated in a screening study for new acetylcholinesterase inhibitors from plant origin and has not been advanced to in vivo or human testing.

6. Body Systems and Health Areas Associated with Quisqualis

Based on the available preclinical and traditional use evidence, Combretum indicum / Quisqualis has been associated with the following body systems and health areas:

• Gastrointestinal system: Anthelmintic use against roundworms and pinworms; relief of diarrhea, dysentery, constipation, and indigestion.
• Metabolic system: Preclinical antidiabetic and lipid-lowering effects in rodent models.
• Immune system: Immunomodulatory, antimicrobial, antioxidant, antipyretic, anthelmintic, antirheumatic, antiviral, antifungal, antiseptic, antidiarrheal, and anti-hyperlipidemic pharmacological properties have been reported.
• Skin and integumentary system: Traditional topical use for boils, ulcers, ringworm, and skin parasites; case reports of photoallergic contact dermatitis.
• Musculoskeletal system: Traditional use for rheumatism and pain.
• Nervous system: In vitro acetylcholinesterase inhibition; the neuroexcitatory properties of quisqualic acid are a dual-edged concern (see Safety section).
• Urinary system: Traditional use for nephritis and dysuria.
• Respiratory system: Traditional use for cough relief and chest diseases.

7. Dosage Forms and Dosages Reported in Studies

Only dosages explicitly stated in identified sources are presented here.

• Sub-chronic toxicity study (rats, oral): The potential repeated dose toxicity and genotoxicity of a standardized Quisqualis indica extract (HU033), an ethanol extract of seeds standardized to 1% quisqualic acid, were determined under good laboratory practice conditions. HU033 was orally administered to Sprague–Dawley (SD) rats at doses of 500, 1000, and 2000 mg/kg/day for 13 consecutive weeks.
• Acute toxicity study (mice, subcutaneous injection): The minimum lethal dosage of the water-soluble extract of C. indicum for subcutaneous injection in mice is 20 g/kg. The single use of C. indicum decoction in mice showed an LD50 in excess of 4 g/kg, indicating extremely low acute oral toxicity.
• Antioxidant in vitro (DPPH assay): The methanolic leaf extract exhibited a dose-dependent scavenging of DPPH with an IC50 of 48.87 µg/ml.
• Acetylcholinesterase inhibition in vitro: The methanolic flower extract inhibited electric eel acetylcholinesterase in a dose-dependent manner with an IC50 value of 0.77 µg/ml.

No standardized or validated human dosage regimens for therapeutic use are established in the peer-reviewed literature. Traditional Chinese Medicine dosing (roasted seeds) is referenced in historical Chinese materia medica, but quantified human clinical dosing data from controlled trials are absent from the available literature.

8. Safety Considerations

8.1 Subchronic Toxicity and Genotoxicity (Preclinical)

In the 13-week repeated oral dose toxicity study, repeated oral administration of HU033 did not result in death or any significant treatment-related adverse effects such as clinical signs, bodyweight, or food/water consumption changes. After 13 weeks of repeated dosing by oral administration, there was no treatment-related adverse clinical sign including food consumption, organ weights, and histopathological findings, or significant decrement in body weight. The genotoxicity of HU033 was determined with a standard battery of genotoxicity tests, including an in vitro bacterial reverse mutation test, an in vitro chromosomal aberration test, and an in vivo micronucleus test.

8.2 Adverse Effects at Therapeutic and Higher Doses (Traditional Reports)

Mildly toxic side-effects include nausea, vomiting, and belching; toasting the herb is reported to decrease its toxicity. Occasionally, allergic reactions occur with skin rashes with or without itching, painful swollen ankles, and increase in body temperature. C. indicum should be taken in small amounts. Large-amount intake or consumption with tea can cause hiccups, dizziness, vomiting, pain in the abdomen, and diarrhea.

Overdose symptoms include headache, dizziness, nausea, vomiting, diarrhea, abdominal pain, sweating, cold limbs, leading to seizures and drop in blood pressure. In large doses, the fruits cause nausea, vomiting, hiccough, and even unconsciousness.

8.3 Neurotoxic Risk of Quisqualic Acid

The seeds contain the chemical quisqualic acid, which is an agonist for the AMPA receptor, a kind of glutamate receptor in the brain. This chemical is linked to excitotoxicity (cell death). Quisqualic acid has shown excitatory effects on cultured neurons as well as in a variety of animal models; it causes various types of limbic seizures and neuronal damage. This toxicological profile of the principal active constituent is a recognized constraint on its use as an anthelmintic, and the prospects for Combretum indicum seeds as an anthelmintic are limited, due to the toxic side-effects of quisqualic acid.

8.4 Photoallergic Contact Dermatitis

A case report published in Contact Dermatitis in 2016 documented photoallergic contact dermatitis caused by Quisqualis indica (Combretum indicum) flowers, with key terms identifying: case report; Chinese honeysuckle; flower; photoallergic contact dermatitis. This indicates that topical or environmental contact with the flowers may be a sensitizing risk in predisposed individuals, particularly under UV exposure.

8.5 Interactions and Contraindications (Historical Record)

The traditional Chinese materia medica sources note that concurrent consumption with tea increases the risk of adverse gastrointestinal effects. Overdose is traditionally treated with a decoction of Caryophylli flos (clove) and Glycyrrhizae radix (licorice root). No systematic drug-herb interaction studies in humans have been identified in the available literature.

9. Summary of Evidence Quality

The overall evidence base for Combretum indicum / Quisqualis as a medicinal or dietary supplement is predominantly preclinical. Pharmacological studies have shown multiple bioactivities such as immunomodulatory, anti-diabetic, anti-inflammatory, antioxidant, antibacterial, anthelmintic, analgesic, anti-dyslipidemic, and anti-asthmatic activities; however, the great majority of these studies are in vitro or in animal models. Due to the wide range of therapeutic properties, the plant is easily accessible and fast growing, giving it great potential for further pharmacological studies and drug development. No large randomized controlled trials in humans have been identified. The anthelmintic use has the longest documented history and strongest pharmacopoeial basis (Chinese Pharmacopoeia), but is constrained by the neurotoxic potential of quisqualic acid, particularly at higher doses. All other proposed therapeutic indications remain at the level of preclinical or traditional evidence and require further rigorous clinical investigation.

References

• Note on the identity and re-naming the genus Quisqualis Linnaeus (Combretaceae) — ResearchGate / Pleione 10(1), 2016
• Quisqualis indica L. — World Flora Online (2026)
• Combretum indicum (L.) DeFilipps — Plants of the World Online, Kew Science
• Quisqualis indica (QISIN) — EPPO Global Database
• Combretum indicum — NCBI Taxonomy Browser
• Combretum indicum — Wikipedia
• Quisqualic acid — Wikipedia
• Quisqualic Acid — ScienceDirect Topics Overview
• Quisqualis indica L. — In: Chinese Drugs of Plant Origin. Springer, Berlin, Heidelberg (1992)
• Combretum Indicum Linn. A Comprehensive Review of Phytochemistry and Pharmacological Properties — IJPS Journal (2026)
• Pharmacoinformatics and UPLC-QTOF/ESI-MS-Based Phytochemical Screening of Combretum indicum against Oxidative Stress and Alloxan-Induced Diabetes in Long–Evans Rats — PMC / Molecules 2021
• Repeated oral dose toxicity and genotoxicity of a standardized Quisqualis indica extract — PMC / Toxicological Research 2022
• Photoallergic contact dermatitis caused by Quisqualis indica (Combretum indicum) — PubMed / Contact Dermatitis 2016
• Quisqualis indica Linn: A review of its medicinal properties — ResearchGate
• Plant description file: Quisqualis indica — Doc Développement Durable
• Combretum indicum — Useful Tropical Plants Database
• Investigation on antioxidant and antimicrobial properties of methanolic extract of Combretum indicum leaf — ResearchGate
• Effect of ethanolic extract of Quisqualis indica L. flower on experimental esophagitis in albino Wistar rats — PubMed
• A comprehensive review of Combretum flavonoids and their biological activities: An update between 1990 and 2022 — ScienceDirect
• Combretum indicum L. DeFilipps — GlobInMed
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• A comprehensive review on Chinese honeysuckle (Quisqualis indica): A Traditional Chinese plant — ScienceDirect (2024)
• A Review on Ethnobotanical, Phytochemical and Pharmacological activities of Quisqualis indica Linn. — Research Journal of Pharmacognosy and Phytochemistry (2017)