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Sweet flag helps to clear the mind and provides relief from mental stagnation

Sweet flag

Acorus calamus Araceae

Vacha, also known as sweet flag, literally means ‘speech’. Calamus thrives in wet, damp marshland and is a semi-aquatic perennial. Its qualities treat similar ‘terrain’ in the whole system; sluggish, congested, heavy and wet conditions, like those of a marshland, are opposed by the warm, drying, penetrating and stimulating qualities of Vacha.

Sustainability Status

Sustainability status

Not currently on risk lists but complete data may be missing on the status of the species. Read more about our sustainability guide.

Key benefits
  • Improves concentration
  • Clears the mind
  • Clears damp, wet coughs

  • How does it feel?

    Vacha is a semi-aquatic plant that grows in damp, marshy locations across the globe, but is native to India. It has long, slender and sword-shaped leaves with creeping rhizomes. The flowers are very small and fragrant and a pale-green in colour and fruits are small and fleshy. It is the rhizomes of the plant that are most important medicinally.

  • What can I use it for?

    The essential oils within vacha are particularly penetrating for the mind, helping to clear the mind and provide relief from mental stagnation.

    An essential oil present in the plant, Beta-asarone, demonstrates relaxant and anti-spasmodic activities within the digestive, respiratory and the urinary system. Components within the rhizome have also demonstrated pain-killing and anti-inflammatory activities within the same three body systems.

  • Into the heart of sweet flag

    The pungent and aromatic essential oils in vacha have made it an excellent herb for the removal of heavy, damp and congested toxicity throughout the body. It is considered to be a stimulant to the nervous system and an aromatic carminative to the digestive system. The activity of the essential oils appears to concentrate within the cerebral hemispheres and the mind, helping to shift emotional congestion that may be influencing stagnant depression and reduced cognitive abilities. This particular quality has made vacha a helpful herb for supporting recovery from stroke, epileptic attacks and loss of speech.

    The primary application of vacha is to open the mind, improve concentration, clarity and speech. Its stimulating effect makes it useful in treating depression and mental sluggishness. It actually scrapes stagnation from the subtle channels of the mind. This acrid root is also used in childhood developmental problems and in post stroke speech difficulties. It specifically strengthens the ability of the mind to receive information and recall from memory.

    The aromatic heating effect of vacha helps to calm the gastric nerves, prevent fermentation and clear excess congestion in dyspepsia, flatulence and borborygmus.

    Vacha clears damp, wet coughs from the lungs. It also has an affinity for the throat and clears ‘obstructions’ from the throat. Its purgative effect on the head make it an excellent remedy for sinus congestion, nasal polyps and rhinitis.

    The decongestant and pungent qualities of vacha have traditionally indicated its use in treating urinary gravel and infections.

  • Traditional actions

  • Traditional energetic actions

    Herbal energetics are the descriptions Herbalists have given to plants, mushrooms, lichens, foods, and some minerals based on the direct experience of how they taste, feel, and work in the body. All traditional health systems use these principles to explain how the environment we live in and absorb, impacts our health. Find out more about traditional energetic actions in our article “An introduction to herbal energetics“.

  • Did you know?

    In India, vacha powder was traditionally mixed with ghee and given to newborn babies on the seventh day to improve speech and help develop the intellect.

Additional information

  • Safety

    No drug-herb interactions are known. Always combine it with other aromatic herbs to offset the emetic nature; e.g. fennel, cardamom and peppermint. It is banned in the USA by the FDA because it contains β-asarone which is considered to be carcinogenic. β-asarone is not present in all varieties.

  • Dosage

    1–5g/day dried root or 1–5ml/day of a 1:5 in 60% tincture.

sweet flag illustration

Related herbs

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Elecampane

Fennel

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Aromatic
An ‘aromatic’ remedy, high in volatile essential oils, was most often associated with calming and sometimes ‘warming’ the digestion. Most kitchen spices and herbs have this quality: they were used both as flavouring and to ease the digestion of sometimes challenging pre-industrial foods. Many aromatics are classed as ‘carminatives’ and are used to reduce colic, bloating and agitated digestion. They also often feature in respiratory remedies for colds, chest and other airway infections. They are also classic calming inhalants and massage oils, and are the basis of aromatherapy for their mental benefits.
Astringent taste
The puckering taste you get with many plants (the most familiar is black tea after being stewed too long, or some red wines) is produced by complex polyphenols such as tannins. Tannins are used in concentrated form (eg from oak bark) to make leather from animal skins. The process of ‘tanning’ involves the coagulation of relatively fluid proteins in living tissues into tight clotted fibres (similar to the process of boiling an egg). Tannins in effect turn exposed surfaces on the body into leather. In the case of the lining of mouth and upper digestive tract this is only temporary as new mucosa are replenished, but in the meantime can calm inflamed or irritated surfaces. In the case of open wounds tannins can be a life-saver – when strong (as in the bark of broadleaved trees) they can seal a damaged surface. One group of tannins, the reddish-brown ‘condensed tannins’ are procyanidins, which can reduce inflammation and oxidative damage.
Bitter
Bitters are a very complex group of phytochemicals that stimulate the bitter receptors in the mouth. They were some of the most valuable remedies in ancient medicine. They were experienced as stimulating appetite and switching on a wide range of key digestive functions, including increasing bile clearance from the liver (as bile is a key factor in bowel health this can be translated into improving bowel functions and the microbiome). Many of these reputations are being supported by new research on the role of bitter receptors in the mouth and elsewhere round the body. Bitters were also seen as ‘cooling’ reducing the intensity of some fevers and inflammatory diseases.
Blue-purple colouring
Any fruits with a blue-purple colouring contain high levels of the polyphenols known as anthocyanins. These work 1) on the walls of small blood vessels, helping to maintain capillary structure to reduce a key stage in inflammation, and improving the microcirculation to the tissues; 2) to improve retinal function and vision; 3) to support connective tissue repair around the body.
Cooling
Traditional ‘cold’ or cooling’ remedies often contain bitter phytonutrients such a iridoids (gentian), sesiquterpenes (chamomile), anthraquinones (rhubarb root), mucilages (marshmallow), some alkaloids and flavonoids. They tend to influence the digestive system, liver and kidneys. Cooling herbs do just that; they diffuse, drain and clear heat from areas of inflammation, redness and irritation. Sweet, bitter and astringent herbs tend to be cooling.
Hot
Traditional ‘hot’ or ‘heating’ remedies, often containing spice ingredients like capsaicin, the gingerols (ginger), piperine (black or long pepper), curcumin (turmeric) or the sulfurous isothiocyanates from mustard, horseradich or wasabi, generate warmth when taken. In modern times this might translate as thermogenic and circulatory stimulant effects. There is evidence of improved tissue blood flow with such remedies: this would lead to a reduction in build-up of metabolites and tissue damage. Heating remedies were used to counter the impact of cold, reducing any symptoms made worse in the cold. .
Mucilaginous
Mucilages are complex carbohydrate based plant constituents with a slimy or ‘unctuous’ feel especially when chewed or macerated in water. Their effect is due simply to their physical coating exposed surfaces. From prehistory they were most often used as wound remedies for their soothing and healing effects on damaged tissues. Nowadays they are used more for these effects on the digestive lining, from the throat to the stomach, where they can relieve irritation and inflammation such as pharyngitis and gastritis. Some of the prominent mucilaginous remedies like slippery elm, aloe vera and the seaweeds can be used as physical buffers to reduce the harm and pain caused by reflux of excess stomach acid. Mucilages are also widely used to reduce dry coughing. Here the effect seems to be by reflex through embryonic nerve connections: reduced signals from the upper digestive wall appear to translate as reduced activity of airway muscles and increased activity of airway mucus cells. Some seed mucilages, such as in psyllium seed, flaxseed (linseed) or guar bean survive digestion to provide bulking laxative effects in the bowel. These can also reduce rate of absorption of sugar and cholesterol. .
New-mown hay aroma
The familiar country odour of haymaking, of drying grass and other plants, is largely produced by coumarins (originally isolated from tonka beans – in French coumarou) and widely used in perfumery. They are chemically categorised as benzopyrone lactones and are important phytochemicals, with strong antioxidant activity in the laboratory and likely effects in modulating inflammation. They were most often associated with the calming effect linked to their use in stuffing mattresses and pillows and plants, high In coumarins were commonly used for these properties.
Resinous
Resins are most familiar as tacky discharges from pine trees (and as the substance in amber, and rosin for violin bows). They were most valued however as the basis of ancient commodities like frankincense and myrrh (two of the three gifts of the Three Wise Men to the baby Jesus) and getting access to their source was one benefit to Solomon for marrying the Queen of Sheba (now Ethiopia). Resins were the original antiseptic remedies, ground and applied as powders or pastes to wounds or inflamed tissues, and were also used for mummification. With alcohol distillation it was found that they could be dissolved in 90% alcohol and in this form they remain a most powerful mouthwash and gargle, for infected sore throats and gum disease. They never attracted much early research interest because they permanently coat expensive glassware! For use in the mouth, gums and throat hey are best combined with concentrated licorice extracts to keep the resins in suspension and add extra soothing properties. It appears that they work both as local antiseptics and by stimulating white blood cell activity under the mucosal surface. They feel extremely effective!
Salty
The salty flavour is immediately distinctive. A grain dropped onto the tongue is instantly moistening and a sprinkle on food enkindles digestion. This easily recognisable flavour has its receptors right at the front of the tongue. The salty flavor creates moisture and heat, a sinking and heavy effect which is very grounding for the nervous system and encourages stability. People who are solid and reliable become known as ‘the salt of the earth'.
Sharpness
The sharp taste of some fruits, and almost all unripe fruits, as well as vinegar and fermented foods, is produced by weak acids (the taste is generated by H+ ions from acids stimulating the sour taste buds). Sour taste buds are hard-wired to generate immediate reflex responses elsewhere in the body. Anyone who likes the refreshing taste of lemon or other citrus in the morning will know that one reflex effect is increased saliva production. Other effects are subjective rather than confirmed by research but there is a consistent view that they include increased digestive activity and contraction of the gallbladder.
Sweet
In the days when most people never tasted sugar, ‘sweetness’ was associated with the taste of basic foods: that of cooked vegetables, cereals and meat. In other words sweet was the quality of nourishment, and ‘tonic’ remedies. Describing a remedy as sweet generally led to that remedy being used in convalescence or recovery from illness. Interestingly, the plant constituents most often found in classic tonics like licorice, ginseng are plant steroids including saponins, which also have a sweet taste.

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