The classification of Herbs in Ayurveda is according to their taste (rasa), their energetic effect (virya), their post-digestive effect (vipaka) and their post-digestive effect (prabhava). The initial taste (rasa) indicates the properties it possesses and the therapeutic effects it will have. Thus, a bitter, astringent taste will have a very different action on the body than a sweet, sour taste or a spicy, pungent taste.
Sweet taste is composed of earth and water and is represented in sugars and starches. It balances vata and pitta, increases ojas and promotes growth in the body. It nourishes and revitalises the body and creates contentment in the mind. It is found in almonds, dates, raisins, honey, fennel, licorice, sesame seeds, marshmallow and slippery elm.
Sour taste is composed of earth and fire and is present in fermented or acidic substances. It is heating and increases digestive power by enkindling agni, the digestive fire. It balances vata, enlivens the mind, increases strength, reduces bloating and gas and promotes salivation. Typically sour substances are lemon, lime, raspberry and alcohol.
Salty taste is composed of water and fire and is present in salty substances and alkalis. It balances vata, increases agni, acts as a sedative and laxative and promotes salivation. Salt is found in kelp, seaweed, celery, Irish moss, sea salt and rock salt.
Pungent taste is composed of fire and air and is present in most spicy, acrid or aromatic substances. It stimulates the digestion, increases appetite, acts as an expectorant, increases circulation, promotes clarity of mind, kills worms, alleviates kapha, reduces weight, clears obstructions, opens vessels and relieves blood stagnation. Pungent herbs and spices include; asafoetida, basil, black pepper, cardamom, cayenne, cinnamon, cloves, coriander, cumin, eucalyptus, garlic, ginger, horseradish, mustard, onions, oregano, peppermint, rosemary, sage and thyme.
Bitter taste is composed of air and ether and balances pitta and kapha. It is detoxifying, antibacterial and anti-inflammatory. It also cleanses the blood and liver, stimulates the digestive fire and scrapes away fat. It is present in bitter herbs and foods such as aloe, dandelion, echinacea, rhubarb, yarrow and yellow dock.
Astringent taste is composed of earth and air and is present in food and herbs of a constricting nature. It balances pitta and kapha, stops diarrhoea, stops bleeding, heals wounds, stops sweating and is anti-inflammatory. Astringent substances include black tea, beans, mullein, pomegranate, raspberry leaves and witch hazel.
Virya is the energy or potency of a herb or spice and can be heating or cooling. It indicates the effect the substance will have on pitta dosha. Sweet, astringent and bitter tastes are cooling whilst salt, sour and pungent are heating. Heating herbs increase pitta but reduce vata and kapha. They create sweating and increase the digestive fire. Cooling herbs reduce Pitta but increase vata and kapha. For pitta they are refreshing and help cleanse the blood as well as calm the mind.
Vipaka is the post-digestive effect the herb or spice will have on the body. Sweet and salty tastes have a sweet or moistening post-digestive effect; sour has a sour or heating post-digestive effect and pungent, astringent and bitter have a pungent or drying post-digestive effect. Sweet tastes are digested during the first (kapha) stage of digestion; in the mouth and stomach. Sour or acidic tastes are digested during the second (pitta) phase of digestion; in the stomach and small intestine. Pungent tastes are digested during the third (vata) phase of digestion; in the colon. Thus, we can determine the long-term effect a herb will have on the body. Sweet vipaka will increase kapha and reduce vata and pitta; pungent will increase vata and pitta and reduce kapha; sour will increase pitta and kapha and reduce vata
Prabhava is a term used to describe herbs and spices that have a ‘special’ potency or effect that is unique to it and does not always correspond to the rasa, virya or vipaka. Thus, a plant may be classified as ‘heating’ according to virya but is generally known to be very effective during high fever. In the west herbalists have classified herbs according to their action on the body:
Alterative: These purify the blood and balance pitta and are mostly cooling and bitter. Typical cooling alterative herbs include: aloe vera, burdock, dandelion, echinacea, manjishta, neem, red clover, sandalwood and yellow dock. Hot, pungent alteratives may also be used if there is an ama condition present. Typical herbs include: black pepper, cayenne, cinnamon, garlic and myrrh.
Anti-parasitical: These destroy worms, bacteria, fungi, yeast infections and ama and are mainly bitter or pungent. Typical herbs include: ajwan, asafoetida, cayenne, black pepper, cloves, garlic, pomegranate, pumpkin seeds, thyme and wormwood.
Aphrodisiacs: These are strengthening, invigorating and rejuvenating to the reproductive system and help nourish all bodily tissues. They also increase the mental energy and improve nerve function. They include; angelica, asafoetida, ashwagandha, asparagus, cloves, fenugreek, garlic, ginseng, gokshura, hibiscus, pippali, rose, saffron, shatavari and wild yam.
Astringent: These are drying and moisture preserving and have a contracting, condensing and compacting effect on the tissues. Astringent herbs can be classified as haemostatic (stop bleeding), anti-diarrhoea and vulnerary (heal wounds). Common haemostatic herbs include: hibiscus, manjishta, marshmallow, nettle, plantain, raspberry, saffron, self-heal, turmeric and yarrow. Common anti-diarrhoea herbs include: blackberry, comfrey, plantain, raspberry and yellow dock. Others, of a more warming nature and more balancing to vata and the digestive system include: black pepper, ginger, haritaki and nutmeg and poppy seeds. Buttermilk and yoghurt may also be used. Vulnerary herbs include: aloe vera, chickweed, comfrey, honey, marshmallow, plantain, self-heal, slippery elm and turmeric. Comfrey, marshmallow, plantain, self-heal and yarrow are haemostatic, anti-diarrhoea and vulnerary.
Bitter tonic: These are cold, dry, catabolic herbs that stimulate the digestion, reduce heat and clear ama and toxins from the body; especially the blood and liver – they are usually given in relatively small quantities to people suffering from pitta related problems. Many are anti-tumorus, anti-bacterial, anti-viral, and anti-parasitical. They include aloe vera, goldenseal, gentian, kutki and neem.
Carminative: These herbs reduce bloating and gas, promote peristalsis and settle the digestion. They work mainly on vata in the digestive tract and help to increase the digestive fire or agni. Typical herbs include: ajwan, asafoetida, basil, bay leaves, calamus, cardamom, cinnamon, cloves, garlic, ginger, nutmeg, oregano, thyme and turmeric. Carminative herbs with a cooling nature are less likely to produce aggravate pitta and include: chamomile, coriander, cumin, dill, fennel, lime, musta, peppermint and wintergreen.
Diaphoretic: These are mostly heating herbs that increase circulation and perspiration. They are good for the initial stages of colds, fevers and flu as they eliminate toxins from the periphery of the body. They help cleanse the subtle channels and capillaries of the body including the lymphatic system, lungs, respiratory system, sinuses and plasma. Cooling diaphoretics also help cleanse the liver and blood. Heating diaphoretics include: angelica, basil, camphor, cardamom, cinnamon, cloves, eucalyptus, ginger, sage and thyme. Cooling diaphoretics include: burdock, chamomile, coriander, horsetail, peppermint and yarrow.
Diuretic: These promote urination and reduce water and toxicity in the body through increasing the action of the kidneys and urinary bladder. They are kapha or pitta reducing herbs and are bitter, astringent or pungent in taste. In regard to pitta they dispel damp heat, cool and purify the blood, reduce acidity, control diarrhoea and dysentery and help in conditions related to the liver and gall bladder. Cooling diuretic include: asparagus, barley, burdock, coriander, dandelion, fennel, gokshura, horsetail, marshmallow, plantain, punarnava and parsley. Heating diuretics include: ajwan, cinnamon, garlic, mustard and parsley.
Emmenagogues: These are pitta balancing herbs that promote the flow of blood and are indicated for problems related to the female reproductive system, especially the menstrual cycle. Cooling emmenagogues include: chamomile, hibiscus, manjishta, musta, raspberry, rose and yarrow. Heating emmenagogues are indicated when causes are more of a vata nature and include: angelica, asafoetida, cinnamon, ginger, myrrh, parsley and turmeric.
Expectorants: These promote the flow of phlegm and mucus from the lungs, nasal passages and stomach and are therefore indicated for colds, flu, cough, asthma, bronchitis and digestive complaints relating to mucus. They mainly help reduce kapha through their drying, warming nature and include herbs such as: calamus, cardamom, cinnamon, cloves, eucalyptus, ginger, pippali and thyme.
Demulcent: These herbs are mucilaginous and alleviate dryness. They are softening, strengthening, nutritive and anti-inflammatory and help feed the mucus membranes and connective tissue to heal wounds, sores and ulcers. They can also act as moistening expectorants in cases of dry cough. Herbs include: bamboo, chickweed, comfrey root, flaxseed, licorice, marshmallow and slippery elm.
Laxative: These are used in cases of constipation and toxins in the colon as they promote bowel movement and peristalsis. Purgatives have a stronger action and are generally cold and bitter; they may cause diarrhoea and gripping and include: aloe vera powder, castor oil, rhubarb and senna. Milder laxatives are used in more general vata conditions and include: bran, flaxseed, ghee, licorice, prunes, psyllium seeds, raisins, shatavari, warm milk and yellow dock.
Nervines: These act upon the nervous system. They either stimulate or sedate the mind and have an anti-spasmodic effect on muscle tissue. They can help with menstrual cramps, headaches, muscle tremors, nerve pain, lumbago and sciatica. Heating nervines pacify vata and kapha dosha and include: asafoetida, basil, calamus, camphor, eucalyptus, garlic, guggul, myrrh, nutmeg, poppy seeds, sage and valerian. Cooling nervines help pacify pitta dosha and include: bhringaraj, chamomile, gotu kola, hops, jatamamsi, mullein, peppermint, sandalwood, St.John’s Wort and wild yam.
Stimulants: These are herbs that promote digestion by stimulating agni, the digestive fire. They are mainly heating and pungent and are the best herbs to increase appetite and digest ama or toxins. They increase energy, stimulate the senses and generally increase pitta and decrease kapha. In excess they can disturb vata. Stimulating herbs include: ajwan, asafoetida, black pepper, cayenne, cinnamon, cloves, garlic, ginger, horseradish, mustard and pippali.
These are the types of herbs in Ayurveda.