Synonyms: Hydrocotyle asiatica – L.
In South Asia, other common names of centella include:
Thalkudi in Oriya; Sarswathi aku in Telugu; Kudavan, (Muththil), or Kudangal in Malayalam; Thankuni in Bengali; Gotu kola in Sinhala; Brahmi in Marathi: Ondelaga in Kannada; Vallaarai in Tamil; Brahmi booti in Hindi; Perook in Manipuri; Manimuni in Assamese;Timare in Tulu; Tangkuanteh in Paite; Brahmabuti or Ghod-tapre in Nepali; and Kholcha ghyan in Newari Nepal Bhasa.
Habitat :Centella asiatica is native to E. Asia – India, China and Japan. Australia. Grows on Old stone walls and rocky sunny places in lowland hills and especially by the coast in central and southern Japan. Shady, damp and wet places such as paddy fields, and in grass thickets
Centella asiatica is an evergreen Perennial plant growing to 0.2m by 1m.
It is hardy to zone 8 and is frost tender.
The stems are slender, creeping stolons, green to reddish-green in color, connecting plants to each other. It has long-stalked, green, reniform leaves with rounded apices which have smooth texture with palmately netted veins. It is in leaf all year, in flower from July to August, and the seeds ripen from August to September. The flowers are hermaphrodite (have both male and female organs) and are pollinated by Insects.
The flowers are pinkish to red in color, born in small, rounded bunches (umbels) near the surface of the soil. Each flower is partly enclosed in two green bracts. The hermaphrodite flowers are minute in size (less than 3 mm), with 5-6 corolla lobes per flower. Each flower bears five stamens and two styles. The fruit are densely reticulate, distinguishing it from species of Hydrocotyle which have smooth, ribbed or warty fruit. The plant is self-fertile. The leaves are borne on pericladial petioles, around 2 cm. The rootstock consists of rhizomes, growing vertically down. They are creamish in color and covered with root hairs.
Prefers a moist to wet soil in sun or partial shade. Plants also grow on walls in the wild and so should tolerate drier conditions[K]. This species is not hardy in the colder areas of the country, it tolerates temperatures down to between -5 and -10°c. It grows and spreads very well outdoors during the summer in most parts of the country and is very easy to increase by division. It can therefore be grown as a summer crop with divisions being taken during the growing season and overwintered in a greenhouse in case the outdoor plants are killed by winter cold.
Seed – sow spring in a greenhouse. Prick out the seedlings into individual pots when they are large enough to handle and grow them on in a greenhouse for their first winter. Plant them out in late spring or early summer of the following year, after the last expected frosts[K]. Division is simple at any time in the growing season, though the spring is probably best[K]. We find that it is best to pot up the divisions until they are rooting away well, though in selected mild gardens it should be possible to plant the divisions out directly into their permanent positions
Edible Parts: Leaves.
Leaves – raw or cooked. Used in salads and in curries. Cooked as a vegetable. An aromatic flavour, we have found them to be rather overpowering in salads when used in any but small quantities.
Gotu kola is an outstandingly important medicinal herb that is widely used in the Orient and is becoming increasingly popular in the West. Its Indian name is ‘Brahmi’ which means ‘bringing knowledge of the Supreme Reality’ and it has long been used there medicinally and as an aid to meditation. It is a useful tonic and cleansing herb for skin problems and digestive disorders. In India it is chiefly valued as a revitalizing herb that strengthens nervous function and memory. The whole plant is alterative, cardio-depressant, hypotensive, weakly sedative and tonic. It is a rejuvenating diuretic herb that clears toxins, reduces inflammations and fevers, improves healing and immunity, improves the memory and has a balancing effect on the nervous system. It has been suggested that regular use of the herb can rejuvenate the nervous system and it therefore deserves attention as a possible cure for a wide range of nervous disorders including multiple sclerosis[K]. Recent research has shown that gotu kola reduces scarring, improves circulatory problems in the lower limbs and speeds the healing process. It is used internally in the treatment of wounds, chronic skin conditions (including leprosy), venereal diseases, malaria, varicose veins, ulcers, nervous disorders and senility. Caution should be observed since excess doses cause headaches and transient unconsciousness. Externally, the herb is applied to wounds, haemorrhoids and rheumatic joints. The plant can be harvested at any time of the year and is used fresh or dried. Another report says that the dried herb quickly loses its medicinal properties and so is best used fresh.
Medicinal Uses and Indications
Wound Healing and Skin Lesions
Gotu kola contains triterpenoids, compounds that have been shown to aid in wound healing. For example, animal studies indicate that triterpenoids strengthen the skin, increase the concentration of antioxidants in wounds, and restore inflamed tissues by increasing blood supply. Because of these properties, gotu kola has been used externally for burns, psoriasis, prevention of scar formation following surgery, recovery from an episiotomy following vaginal delivery of a newborn, and treatment of external fistulas (a tear at or near the anus).
Venous Insufficiency and Varicose Veins
When blood vessels lose their elasticity, blood pools in the legs and fluid leaks out of the blood vessels, causing the legs to swell (venous insufficiency). In a study of 94 people with venous insufficiency, those who took gotu kola reported a significant improvement in symptoms compared to those who took placebo. In another study of people with varicose veins, ultrasound examination revealed improvements in the vascular tone of those who took gotu cola.
High Blood Pressure
In a study of people with heart disease and high blood pressure, those who took abana (an Ayurvedic herbal mixture containing gotu kola) experienced a significant reduction in diastolic blood pressure (pressure on blood vessels when the heart is at rest) compared to those who took placebo. Further studies are needed to determine whether gotu kola alone, some other herb in the Ayurvedic mixture, or the particular combination of all the herbs in the remedy is responsible for the beneficial effect.
Triterpenoids (active compounds in gotu kola) have been shown to soothe anxiety and boost mental function in mice. A recent study found that people who took gotu kola were less likely to be startled by a novel noise (a potential indicator of anxiety) than those who took placebo. Although the results of this study are somewhat promising, the dose used in this study was extremely high, making it difficult to draw any conclusions about how gotu kola might be used by people with anxiety.
One study involving 13 females with scleroderma found that gotu kola decreased joint pain, skin hardening, and improved finger movement.
Because of sedative effects demonstrated in animals, gotu kola has been used to help people with insomnia.
Dosage and Administration :
Gotu kola is available in teas, as dried herbs, tinctures, capsules, tablets, and ointments. It should be stored in a cool, dry play and used before the expiration date on the label.
There is currently no information in the scientific literature about the use of gotu kola for children. Therefore, it is not recommended for those under 18 years old.
The adult dosage of gotu kola may vary depending on the condition being treated. An appropriately trained and certified herbalist, such as a naturopath, can provide the necessary guidance.
The standard dose of gotu kola varies depending on the form:
Dried herb to make tea, add Â¼ to Â½ tsp dried herb to a cup of boiling water (150 mL) for 10 minutes, 3 times a day
Powdered herb (available in capsules) 1,000 to 4,000 mg, 3 times a day
Tincture (1:2, 30% alcohol) 30 to 60 drops (equivalent to 1.5 to 3 mL â€“ there are 5 mL in a teaspoon), 3 times a day
Standardized extractâ€”60 to 120 mg per day; standardized extracts should contain 40% asiaticoside, 29% to 30% asiatic acid, 29% to 30% madecassic acid, and 1% to 2% madecassoside; doses used in studies mentioned in the treatment section range from 20 mg (for scleroderma) up to 180 mg (in one study for venous insufficiency; although, most of the studies for this latter condition were conducted using 90 mg to 120 mg per day).
The recommended dosage for people with insomnia is Â½ tsp of dried herb in a cup of water taken for no more than 4 to 6 weeks.
The use of gotu kola for more than 6 weeks is not recommended. People taking the herb for an extended period of time (up to 6 weeks) should take a 2-week break before taking the herb again.
Asiaticoside, a major component of gotu kola, has also been associated with tumor growth in mice. Though more studies are needed, it is wise for anyone with a history of precancerous or cancerous skin lesions such as squamous cell, basal cell skin cancer, or melanoma to refrain from taking this herb.
Side effects are rare but may include skin allergy and burning sensations (with external use), headache, stomach upset, nausea, dizziness, and extreme drowsiness. These side effects tend to occur with high doses of gotu kola.
Pregnancy and Breastfeeding
Pregnant women should not take gotu kola because it may cause spontaneous abortion. There is little or no information regarding the safety of this herb during breastfeeding, so nursing mothers should refrain from taking this herb.
People older than 65 years should take gotu kola at a lower than standard dose. The strength of the dosage can be increased slowly over time to reduce symptoms. This is best accomplished under the guidance of an appropriately trained and certified herbalist such as a naturopathic doctor.
Interactions and Depletions
There have been no reports documenting negative interactions between gotu kola and medications to date. Since high doses of gotu kola can cause sedation, individuals should refrain from taking this herb with medications that promote sleep or reduce anxiety.
The information presented herein is intended for educational purposes only. Individual results may vary, and before using any supplements, it is always advisable to consult with your own health care provider.