Oak bark, from the common oak tree, has been used as a medicine since ancient times and its virtues were recorded by Dioscorides between about 50 to 70 AD in his fundamental work, De materia medica, a five-volume Greek encyclopedia about herbal medicine and related medicinal substances (a pharmacopoeia). In the spirit of traditional medicine, the principal uses according to Dioscorides are still relevant today: stomach problems, dysentery, spitting blood and bleeding from the womb. The German Commission E approved oak bark for coughs and chronic bronchitis, general inflammation in the mouth or pharynx as well as diarrhoea. Dr Rudolf Weiss recommends a compress for weeping eczema, ulcers on the legs, contact dermatitis in the early weeping stage, inflammatory eye conditions and inflamed haemorrhoids. 

Oak bark contains a high percentage of tannins which give it powerful astringent properties, toning mucous membranes throughout the body and protecting them from irritation and infection. These compounds bind with tissue proteins making them impermeable to bacterial invasion and infection while at the same time strengthening the tissues. By clearing catarrh, and toning mucous membranes in the digestive tract, it aids digestion and absorption. By toning muscles throughout the circulatory system it is useful for haemorrhoids and varicose veins. When taken internally oak bark acts as a diuretic flushing excess fluid from the body. This helps flush out kidney stones and treats bladder infections by increasing urinary output. Externally, a cold compress can be made with the liquid extract to help speed up the healing process for minor wounds, cuts, scrapes, burns, mouth ulcers and herpes. Oak bark should not be used long term. 

Oak is an impressive tree both in terms of its imposing appearance and its longevity. It can live for more than a millennium according to some sources and grow up to 40m high. The doctrine of signatures states that a plant’s shape, colour, markings or essence is a visual clue to the organ or bodily function that the plant has the capacity to heal. According to Matthew Wood instead of tedious memorisation of the various uses of a plant, the doctrine of signatures offers in many (though not all) cases a reliable system of connecting the herb with its remedial use through symbolic association. “In traditional herbalism, especially before the advent of writing, herbal knowledge was often passed on by the use of signatures, to help the student understand the logic of the plant and remember its use.” Wood suggests oak’s signature is the Earth element (cold and dry). “Earthly processes are slow and grounded. They provide the primal bedrock on which life is to be built…The root is the Earth element part of the plant because it goes downwards, into the ground, and it interacts with the mineral realm. Thus, plants that have large roots, heavy, thick barks, and powerful structure are Earth plants, like the oak tree. The oak sends down a huge root system which is usually about twice the circumference of the above-ground canopy of the plant. Above the earth it produces powerful, thick, strong wood covered with a heavy, strong bark. Barks are usually associated with tannins, the puckering agents that provide our astringents in herbalism. Hence, oak is a powerful astringent.  It is puckering, contracting, strengthening, and consolidating like the Earth element.”

References

Wood M. The Book of Herbal Wisdom. California:North Atlantic Books. 1997.

Weiss R. Herbal Medicine.Stuttgart: Thieme, 2001. p. 110-11.

McIntyre A. The Complete Woman’s Herbal. Gai Books Limited:London. 1994. p. 157

Wood M. The Doctrine of Signatures. Hpathy Medical Publishers c2023 (updated 17 Oct 2016; accessed 17 May 2023). Available from https://hpathy.com/homeopathy-papers/the-doctrine-of-signatures/

Prickly ash is an aromatic tree that, as its name suggests, is covered with very strong prickles. Its bark has a rich history of use as a herb for stimulating the circulation, the lymphatic system and mucous membranes. Another common name for Zanthoxylum is yellow wood, zanthos being the Greek word for yellow. The berries of this North American tree are being investigated as a suitable substitute for Sichuan pepper (from various species of Chinese prickly ash), which is the foundation flavour in five spice powder used in Asian cooking. Prickly ash is also commonly known as toothache tree, or tickle tongue, due to the analgesic properties of its bark. Native cultures from around the world including Native American, African, South Asian and Chinese traditions have used prickly ash to treat toothache, arthritis and pain for hundreds of years. New Zealand medical herbalist Richard Whelan says: “Simply take a small amount of prickly ash tincture, drip it into a wad of cotton until soaked, and hold directly against the sore tooth. Pain should be relieved within minutes.” The two most common sites of treatment by prickly ash, the teeth and joints, are richly innervated by pain fibres, suggesting that chemicals within prickly ash may directly target peripheral pain neurons.

The same compounds that give echinacea its characteristic numbing tingle, alkylamides, are found in prickly ash bark as well. Alkylamides are secondary metabolites found in several medicinal plants belonging to different families. Plants containing alkylamides are used as spices for their pungent and tingling sensations. According to researchers “Zanthoxylum bark, leaves, and fruit capsules pack a one-two punch of [flavour] and tongue-numbing. As a member of the Rutaceae, the family that includes oranges, grapefruits, and kumquats, the citrusy [flavours] of limonene, citronellal, methyl cinnamate, and cineol are expected, but the numbing property is unique to the genus. That anesthetic response is due to alkamides derived from polyunsaturated carboxylic acids, most likely tetradecapentaenoic acid with isobutylamin, also known as hydroxy sanshool. Sanshool apparently acts like some other [anaesthetics] by activating sensory neurons and inhibiting background potassium conductance.”

As a circulatory stimulant prickly ash is used when there is sluggish circulation such as in chilblains, cramps in the legs (including night cramps), varicose veins, varicose ulcers, Raynaud’s syndrome and erectile dysfunction. It is also indicated in other chronic inflammatory disorders marked by deficient circulation such as joint diseases like rheumatism and arthritis. It is said to be similar to cayenne (Capsicum frutescens) although slower in action. It combines well with devil's claw (Harpagophytum procumbens) for arthritis and with ginger (Zingiber officinale) to improve circulation and help shift deep-seated conditions in the joints or tissues.

References

Maier K. Energetic Herbalism. Vermont: Chelsea Green Publishing. 2021. p. 293

Putz FE, Patel N. Florida Szechuan pepper: A financial opportunity. The Palmetto. 2019;35: 4-7.

Tsunozaki M, Lennertz RC, Vilceanu D, Katta S, Stucky CL, Bautista DM. A 'toothache tree' alkylamide inhibits Aδ mechanonociceptors to alleviate mechanical pain. J Physiol. 2013 Jul 1;591(13):3325-40. doi: 10.1113/jphysiol.2013.252106. Epub 2013 May 7. PMID: 23652591; PMCID: PMC3717230.

Oxymels are classic, but often overlooked, sweet tasting liquid medicines used to improve the flavour of pungent herbs, especially garlic and cayenne, with the added bonus of having a soothing effect on the mucous membranes. Oxymels contain honey and vinegar which have antimicrobial and expectorant actions respectively. This makes these sweet and sour preparations specific for the treatment of respiratory symptoms. They are an ancient form of medicine dating back as far as the Greek physician Hippocrates (460-370 BC). In his, On Regimen in Acute Diseases, Hippocrates said: “You will find the drink, called oxymel, often very useful… for it promotes expectoration and freedom of breathing”.

Perhaps the most famous oxymel is fire cider, a fortifying spicy tonic most popularly championed by esteemed herbalist Rosemary Gladstar, who coined the phrase in the 1970s. Her recipe included fresh horseradish, onion, garlic, ginger and cayenne. Fire cider gained notoriety when it was recently the subject of an American federal court case over the right to keep traditional remedies trademark-free. In 2019, after a five year battle, it was found that “fire cider” is free from trademark restrictions and is officially considered a generic term, which means no one can own it. This was a landmark victory, supported by Gladstar, setting a precedent so that other herbal products and terms with a history of being commonly shared, and community owned, will be far less likely to be trademarked in the future.

Preparing fire cider at home is a common gateway into herbalism and for many practitioners this herbal staple is their favourite wintertime remedy because it is immune building and sinus clearing. While it’s not for the faint hearted (the cayenne can pack a potent punch) it’s a good brew to have on hand when the cold and flu season approaches to give the immune system a powerful kick. It can be used as a preventative (taken from mid-autumn and throughout the winter months) or taken for acute immune support at the first sign of cold symptoms. It can also stimulate digestion and circulation, which can be warming on cold winter days. The warming herbs are what put the fire in the cider and honey is added to mellow the hot flavours.

Now is the season to make fire cider. The original fire cider can take a month or more to brew because it uses fresh plant material, so we have solved this problem by concocting a timesaving recipe for instant fire cider using liquid herbal extracts – brown bottle herbalists rejoice. Somewhat like chicken soup, there is a lot of flexibility in making fire cider. Every herbalist has their own recipe which can be adjusted according to taste or the kind of wellness support needed. Other herbs often included are turmeric (Curcuma longa), elderberry (Sambucus nigra), cinnamon (Cinnamomum verum), echinacea (Echinacea spp.), astragalus (Astragalus membranaceus), rose hips (Rosa canina), rosemary (Rosmarinus officinalis) and lavender (Lavandula angustifolia). Fire cider is also a tasty condiment and can be combined with olive oil to make a zesty salad dressing.

Fire cider is easy to make, convenient to dose and a delight to the tastebuds. Below is a base recipe:

Ingredients:

¾ cup organic raw apple cider vinegar

¾ cup organic raw honey

90mL Herbal Extract Company Garlic (Allium sativum)

60mL Herbal Extract Company Horseradish (Armoracia rusticana)

40mL Herbal Extract Company Thyme (Thymus vulgaris)

10mL Herbal Extract Company Ginger (Zingiber officinale)

2mL Herbal Extract Company Cayenne (Capsicum frutescens) (Can be adjusted according to taste, e.g. 1mL for those who prefer less heat.)

Instructions:

Combine the apple cider vinegar and honey in a pot and gently warm to the consistency of a syrup.

Remove from the heat and add the herbal extracts.

Stir well to combine.

Pour into a 500mL amber glass bottle and label.

Store in a cool, dark place (for up to a year) or in the fridge to extend the shelf life. Gently shake before using. Enjoy.

Yield: 500mL

Maintenance Dose: 10mL shot once or twice a day.

Acute immune support: 10mL every 3-4 hours during an active infection.

It can be diluted with a small amount of water if desired or added to hot water with fresh lemon as a tea. Fire cider is best for cold and damp tissue states. Do not give to children under 12 months old.

References

De la Foret R. Alchemy of Herbs. Hay House:California. 2017 p.173

Adams J, Tan E. Herbal Manufacturing. Preston:Northern Melbourne Institute of Tafe. 2006. p. 60

Zargaran A, Zarshenas MM, Mehdizadeh A, Mohagheghzadeh A. Oxymel in medieval Persia. Pharm Hist (Lond). 2012 Mar;42(1):11-3. PMID: 22530314.

Hippocrates. ON REGIMEN IN ACUTE DISEASES. Western Standard c1999-2023 (updated 400BC; accessed 20 Apr 2023). Available from https://www.originalsources.com/Document.aspx?DocID=JR36KUK3RJ5RNWA

Bauman H. Free Fire Cider: Traditional Remedy Remains Generic after Landmark Case. Herbalgram. Spring 2020;125:58-65.

Gladstar R. Tradition Not Trademark: Fire Cider Goes to Court. c2023 Storey Publishing (accessed 17 April 2023). Available from https://www.storey.com/article/tradition-not-trademark-fire-cider-court/

Ngozi A. How To Make Homemade Fire Cider (With Video!). The Herbal Academy. (updated 21 Dec 2016: accessed 14 Apr 2023).  Available from https://theherbalacademy.com/homemade-fire-cider/

Troubleshooting Fire Cider: Answering Your Questions. The Herbal Academy. (updated 7 Oct 2022: accessed 20 Apr 2023). Available from https://theherbalacademy.com/troubleshooting-fire-cider/?awt_a=5cXw&awt_l=FXTqr&awt_m=3ex5.dYToNG43Xw

The results of a February 2023 study suggest that bacopa (Bacopa monnieri) can improve emotional function in Parkinson's disease patients however further clinical trials are needed to confirm this possibility. Parkinson’s disease is a disorder of the nervous system. It results from damage to the nerve cells that produce dopamine, a chemical that is vital for the smooth control of muscles and movement. It causes unintended or uncontrollable movements such as shaking, stiffness and difficulty with balance and coordination, along with a range of mental health issues such as depression, anxiety, memory problems and dementia. This clinical trial assessed the effects of bacopa on parameters that are related to Parkinson's disease. Bacopa is a cognitive enhancing Ayurvedic herb known to be effective in neurological disorders since ancient times. A 2019 research paper on bacopa found that, overall, studies have concluded that bacopa can be used for the treatment of Alzheimer's disease and other brain disorders.i ii

In the Brazilian pilot study 20 volunteers with Parkinson's disease were recruited for a primary, interventional, controlled, parallel, double-blind clinical study. The volunteers were assigned to treatment with either bacopa (225 or 450mg/day) or placebo. The Parkinson's Disease Quality-of-Life questionnaire was applied, and motor activity was assessed before treatment and 30, 60 and 90 days after treatment with the bacopa or placebo.

There were time-dependent improvements in emotional function with bacopa treatment at the daily dose of 450mg. A strong correlation was found between quality of life and movement outcomes at baseline and 30 days of treatment with bacopa, and a moderate correlation for 60 and 90 days of treatment with bacopa when compared with baseline time.

References

Dubey T, Chinnathambi S. Brahmi (Bacopa monnieri): An ayurvedic herb against the Alzheimer's disease. Arch Biochem Biophys. 2019 Nov 15;676:108153. doi: 10.1016/j.abb.2019.108153. Epub 2019 Oct 14. PMID: 31622587.

Santos AFD, Souza MMQ, Amaral EC, Albuquerque ER, Bortoloti DS, Gasparotto Junior A, Lourenço ELB, Lovato ECW, Lívero FADR. Bacopa monnieri in Patients with Parkinson's Disease: A Pilot Study. J Med Food. 2023 Feb;26(2):114-119. doi: 10.1089/jmf.2022.0106. PMID: 36800346.

The Difference Between Black Cohosh (Actaea racemosa) and Blue Cohosh (Caulophyllum thalictroides).

Both black and blue cohosh share a similar common name, American Indian heritage and their roots have historically been used to treat women's health conditions however the similarities end there. In fact the two herbs, which bear little physical similarity to one another, do not even come from the same genus and family of plants. According to the American Herbal Pharmacopoeia (AHP) blue cohosh monograph “these are taxonomically unrelated plants that are not typically confused.” Previously known as Cimicifuga racemosa, black cohosh is from the Ranunculaceae, or buttercup, family making it a cousin of pulsatilla (Anemone pulsatilla) which it has similarities to and can be substituted for. It is a tall hardy wildflower which has long, wand-like white flowers. Blue cohosh is from the Berberidaceae, or barberry family. The plant has dark blue berries and small, white flowers. According to Lloyd and Lloyd (1931), ‘cohosh’ is an Algonquin Indian word meaning ‘it is rough’ (with hairs).

Black cohosh is considered ‘the menopause herb’ however it also has a long history of being used for the nervous system. While it is useful for stressed menopausal women its anodyne and sedative properties can help nerve and muscle pain. Black cohosh is effective in relieving headaches, tinnitus, menstrual cramps and symptoms brought about by hormonal imbalances.

Blue cohosh is generally classed as a uterine tonic. Historically it was used to prepare the uterus for labour (partus praeparator), for period pain and for various ‘inflammations’ of the uterus. It is used most commonly in pregnancy and gynaecology, most specifically as a way to avoid conventional methods of induction. Case reports of adverse events in recent years, however, have called for an evaluation of the plant’s pharmacological and safety data. The AHP monograph says ”it may still prove to be a safe and effective induction agent when used by highly trained and experienced birthing professionals, but concern regarding potential toxicity has limited its use in birthing.” A review of the data suggests that blue cohosh is indeed associated with certain adverse events reported, but confounding factors make it impossible to establish a causal relationship. The monograph stressed the “need to use the herb within the context of those most experienced with it and in the context of how it was most widely used traditionally, in combination with other botanicals.” A combination of blue and black cohosh has been shown to be effective in ripening the uterus for augmenting labour. There were claims of neurological toxicity in a newborn after using this combination however they were formally disputed on the grounds that the toxic effects suggested would only occur if much higher doses than reported were consumed. Caution is therefore advised with this herb during pregnancy.

References

Blue Cohosh Root & Rhizome monograph. American Herbal Pharmacopoeia. 2012.

HEC black cohosh monograph

Smith T. American Herbal Pharmacopoeia Publishes Blue Cohosh Monograph. HerbalGram Winter 2012;96:18. https://www.herbalgram.org/resources/herbalgram/issues/96/table-of-contents/hg96-orgnews-blkcohosh/

Trickey R. Women, Hormones and the Menstrual Cycle. 3rd edn. Fairfield: Melbourne Holistic Health Group. 2011. p. 293

Medicinal hydrangea is a wild variety and has little in common with the dramatic blue and pink garden hydrangeas with their showy pompom flower heads. It is also known by the common name seven barks which refers to the peculiar characteristic of its stem bark, which peels off in seven thin layers of different colours. The genus name Hydrangea means water vessel. While this refers to hydrangea being a marsh or aquatic plant, it also attests to its medicinal activity.   

Hydrangea root is a diuretic herb traditionally used by Cherokee Indians for improving the health of both the bladder and the kidney, which remove excess water and waste from the body. It is reputed to be effective in a large range of urinary problems such as urinary stones and infections, including cystitis and urethritis. Internationally renowned herbalist David Hoffman says hydrangea’s greatest use is in the treatment of inflamed or enlarged prostate glands. Hoffman’s contemporary and author of The Essential Book of Herbal Medicine, Simon Mills, agrees saying: “However it is for prostatitis that it has been most recommended. It may be seen as a useful complement to saw palmetto (Serenoa repens) and/or damiana (Turnera diffusa) in supportive prescriptions for senescence [the process of growing old] and infirmity in men.” In her modern herbal classic Common Herbs for Natural Health, the late Juliette de Bairacli Levy adds that it is “a mild and soothing herb, effective in rheumatic troubles and glandular disorders.”        

In her eponymous book about herbal medicine (1988), the late Dorothy Hall included hydrangea in her materia medica of person pictures. She called it the “messy divorce” herb: “Hydrangea can become set in a pattern of bitterness and cynicism…often holding on to grudges, resentments and old hurts…if you don’t want to carry a load of heavy stones in your emotional water vessel, hydrangea may be a necessary ingredient in your individual mixture.” Hall prescribed hydrangea with herbs such as horsetail (Equisetum arvense) and uva ursi (Arctostaphylos uva-ursi) to soften, chemically change or loosen gravel and stone. Hoffman combines it with uva ursi and gravel root (Eupatorium purpureum) for kidney stones and horsetail for prostate problems.

References

Grieve M. A Modern Herbal. Middlesex:Penguin Books. 1978. p. 424

Hylton, W ed. The Rodale Herb Book. Rodale Press, 1974. p. 474 http://www.botanical.com/botanical/mgmh/h/hydran45.html

Hoffmann D. The New Holistic Herbal. Element:Dorest. 1990. p. 207

Mills S. The Essential Book of Herbal Medicine. Penguin:London. 1991. p.520

de Bairacli Levy J. Common Herbs for Natural Health. Ash Tree Publishing:New York. 1997. p.87

Hall D. Dorothy Hall’s Herbal Medicine. Sydney:Lothian. 1988. p. 203-6

A member of the nightshade family (Solanaceae), along with potatoes, tomatoes and eggplants, Capsicum frutescens is also known as cayenne pepper, or tabasco pepper, whereas Capsicum annum is known as, depending on the variety, paprika, chilli or capsicum (the larger, bell shaped fruit that has a sweet taste). To say cayenne is hot is an understatement. It packs a potent punch that knocks your socks off. This thrills some and dismays others. The modern use of the word “spicy” as a synonym for “hot” is almost entirely the fault of cayenne. Despite its potency cayenne is perhaps one of our most underestimated herbs. Dr. Richard Shulze, one of America’s foremost authorities on herbal medicine says “If you master only one herb in your life, master cayenne pepper. It is more powerful than anything else.” Energetically it is dramatic, being intensely warming and drying. This means it is best suited to people who tend to be cool.

The fruit pungency is due to alkaloid compounds known as capsaicinoids. They are commonly called capsaicin because it is the most prevalent among the seven capsaicinoids. It is thought this alkaloid evolved, as did many other plant alkaloids, as a protection against predators. Since capsaicin is oil soluble and not soluble in water, drinking it does not help relieve the hot sensation. Instead, thick cream, milk or yoghurt is said to neutralise the burn. This is not only due to the fats present but also the casein, a protein found in dairy products, which strips the capsaicin molecules from the receptors and “puts out the fire”. Pungency is dependent on the genetic makeup of the plant and other environmental factors. Among the cultivated peppers C. frutescens is the highest and C. annuum is the most variable in pungency.

Cayenne is a circulatory stimulant that can be taken internally in very small amounts, or applied topically, to enhance circulation and blood flow. It can be used for cold hands and feet when there is insufficient peripheral circulation, for debility, warding off colds and to support a healthy heart. It may also be useful for weight loss where it increases satiety, and therefore may be helpful in preventing overeating. The pungent principles are thought to stimulate and aid digestion, useful for flatulent dyspepsia, and to act as a counterirritant when applied externally, in the form of a cream, ointment or plaster, for problems such as rheumatic pains where it has a paradoxical action. A recent Cochrane review found that when cayenne is topically applied as a plaster or cream it appears to reduce pain more than placebo and could be considered as a treatment option for chronic low back pain.

References

de la Forêt R. Cayenne Monograph. Herb Mentor c2023 LearningHerbs.com (updated 5 Apr 2021; accessed 3 Apr 2023). Available from https://herbmentor.learningherbs.com/herb/cayenne/

Mills S. The Essential Book of Herbal Medicine. Penguin:London. 1991. p.421

Saleh BK, Omer A, Teweldemedhin B. Medicinal uses and health benefits of chili pepper (Capsicum spp.): a review. MOJ Food Processing & Technology. 2018;6.

O’Connell J. The Book of Spice. Profile Books:London. 2015 p.67

Bynum H, Bynum W. Remarkable Plants That Shape Our World. Thames & Hudson:London. 2014. p.66.

Saleh BK, Omer A, Teweldemedhin B. Medicinal uses and health benefits of chili pepper (Capsicum spp.): a review. MOJ Food Processing & Technology. 2018;6.

Due to a shortage of black walnut raw material from the recent harvest out of the USA, owing in part to limited pickers, we would like to provide you with some alternative herbs. 

Traditionally black walnut leaf was used as a laxative and vermifuge to help remove intestinal pinworms and threadworms. As an alterative is also useful in the treatment of skin diseases such as acne, cold sores, warts, eczema, psoriasis and ulcers which do not heal quickly. Black walnut is a cousin to butternut (Juglans cinerea), or white walnut, which has similar actions and the same procurement issues.

Clove (Syzygium aromaticum): Clove is typically used alongside black walnut and wormwood (Artemisia absinthium) to take care of parasite eggs which can hatch later and cause re-infection.

Garlic (Allium sativum): Garlic is an effective remedy against bacterial, fungal, viral and parasitic infections. In the digestive tract it has been found that garlic will support the development of the natural bacterial flora whilst killing pathogenic organisms.

Nigella (Nigella sativa): While the panacea herb, nigella, might not be the first herb to think of as a substitute for black walnut it has been used traditionally for the treatment of a variety of disorders, diseases and conditions relating to the digestive tract and liver function. A tincture prepared from the seeds has been used in the treatment of worms and skin eruptions.

Wormwood (Artemisia absinthium): Wormwood is a potent bitter herb used, as the name suggests, to expel intestinal worms. It promotes the appetite and enhances digestion by stimulating peristalsis and increasing the secretion of digestive enzymes and bile from the liver and gallbladder. It is an excellent remedy for dyspeptic complaints including stomach disorders, gastritis, liver and gallbladder ailments. It also has a general tonic action.

Yellow dock (Rumex crispus): Yellow dock has a long history of use for stimulating liver function. It has a powerful cleansing and cooling effect on the body making it an excellent remedy for inflammatory skin problems such as eczema and psoriasis. The bowel cleansing action of yellow dock is very mild, and it is generally considered one of the safest herbs to use long term when the liver and bowel need some stimulation. It is a mild version of cascara sagrada (Frangula purshiana) or rhubarb (Rheum palmatum), which could also be used as substitutes for black walnut.

References

SPetre A. Black Walnuts: A Nutritious Nut Reviewed. Healthline Media a Red Ventures Company c2005-2022 (updated 29 March 2019; accessed 21 Nov 2022). Available from https://www.healthline.com/nutrition/black-walnut#uses

Hoffmann D. Medical Herbalism. Rochester: Healing Arts Press. 2003. p. 526

Ahmad A, Husain A, Mujeeb M, Khan SA, Najmi AK, Siddique NA, Damanhouri ZA, Anwar F. A review on therapeutic potential of Nigella sativa: A miracle herb. Asian Pac J Trop Biomed. 2013 May;3(5):337-52. doi: 10.1016/S2221-1691(13)60075-1. PMID: 23646296; PMCID: PMC3642442.

Wood M. The Book of Herbal Wisdom. California:North Atlantic Books. 1997.

McIntyre A. The Complete Woman’s Herbal. Gai Books Limited:London. 1994. p. 128

Mills S. The Complete Guide to Modern Herbalism. Thorsons:London. 1994. p.444