Candida are a group of commensal fungal species that are common human disease causing microorganisms. They are progressively becoming the most important fungal pathogens affecting humans, causing both internal and external disease. They occupy the mucosal and skin layers of the body resulting in local and systemic illness. There are several types of candida infections categorized according to body location.

Types of Candidiasis:

  1. Oral Thrush: Thrush is an infection of the oral cavity by the causative agent C. albicans. It may affect the lips, the insides of the cheeks, the tongue surface and roof of the mouth. Underlying disease is an important factor contributing to candida infection such as when the immune system is suppressed due to cancer or AIDS. However, thrush may occur in people with healthy immune systems particularly in diabetics and those who use dentures. It presents as curd-like white patches inside the mouth that are typically pronounced on the tongue and roof of the mouth. These patches may bleed when scraped exposing a red and inflamed area. Furthermore, the corners of the mouth may also become red and cracked when the infection is localized around the lips.
  2. Esophagitis: Candidal esophagitis is typically an invasion of thrush into the esophagus. Individuals with esophageal candidiasis may present with difficulty swallowing or painful swallowing, substernal pain (behind the breast bone), gastroesophageal reflux, or nausea without substernal pain. It is commonly associated with cancer and AIDS resulting from the decreased function of the immune system.
  3. Cutaneous: A skin infection from candida will present as red rashes affecting moist and enclosed areas such as from diapers, gloved hands and around the groin, fingernails and skin folds. It causes red, moist, weepy skin lesions with peripheral pustules around the area of infection. In addition there may be burning and itching and a well defined, pronounced red appearance of the affected area.
  4. Vaginal: Vaginal candidiasis is a common female infection affecting approximately 75% of women in their lifetime. Risk factors include pregnancy, uncontrolled diabetes mellitus, broad-spectrum antimicrobial treatment, corticosteroid use, and HIV infection. Symptoms may include vaginal itching, burning discharge, thick white curd-like discharge, and painful intercourse. The birth control pill, antibiotics and frequent douching all contribute to candida growth and frequency of infection.
  5. Systemic Candidiasis: Systemic infections may result from the progression of a localized candida infection. It represents a serious and potentially life-threatening illness that usually requires immediate intervention. Progression of the infection may include internal organs, the spinal column and brain. Symptoms may include shock, decreased kidney output, fever, disseminated intravascular coagulation, and meningitis.

Candida Related Complex (CRC)?

A contentious issue in the medical community is candida related complex, also know as chronic candidiasis or candida hypersensitivity syndrome. There has been no consensus on whether it is a valid diagnostic syndrome, however a collective body of clinical information suggests that there is reason to acknowledge its presence. Unfortunately, there have been very few clinical studies examining this issue and most are speculative or unverifiable. What is known has been popularized by Dr. William Crook, M.D., based on his observations and classifications examining the role of candida in chronic illness, especially when associated with gastrointestinal symptoms. The clinical manifestations of CRC include:

  1. Vaginal Infection: recurrent candida infections of the vagina leading to symptoms of burning, itching and abnormal discharge.
  2. Gastrointestinal Symptoms: such as gas, bloating, diarrhea, abdominal pain, constipation, and heartburn.
  3. General Symptoms: fatigue, lethargy, headache, and irritability.
  4. Respiratory: rhinitis, sneezing and/or wheezing.
  5. Nervous System: numbness, burning, tingling, depression, anxiety, memory disturbances and decreased ability to concentrate.
  6. Menstrual: such as endometriosis, premenstrual tension, cramps and other menstrual irregularities.
  7. Skin: hives, athlete’s foot, fungal infections of the nails or groin, psoriasis and other chronic rashes.

CRC represents a cluster of symptoms and findings that possibly indicate an underlying candida infection. However, similar clinical manifestations may occur in other disease processes, therefore diagnosis of CRC may be difficult and exclusion of other diagnoses may be necessary.

Predisposing Factors:

There are several factors that contribute to candida growth even in relatively healthy individuals such as:

  • Diabetes mellitus
  • Antibiotic use
  • Hospital/In office procedures such as catheterization
  • Corticosteroid use
  • Pregnancy
  • Endocrine disorders
  • Hot weather
  • Restrictive clothing
  • Poor hygiene
  • Birth Control Pill

Diagnosis: The basis of diagnosis includes presenting symptoms, physical exam findings and laboratory testing. In the case of skin related candida infections, a sample may be collected by scraping the skin and then applying a potassium hydroxide solution in order to identify hyphal and budding cells under microscopy. Vaginal and oral candidiasis determination is based on clinical findings such as white curd-like patches, but may also include scrapings and potassium hydroxide application examined under microscopy. Systemic dissemination, which may be fatal, requires rapid identification through blood testing, fluid cultures and microscopy.  Candida related complex or candida sensitivity may be determined based upon IgG, IgM or IgA immunoglobulins, candida immune complexes, or stool culture and microscopy to determine the presence of candida.


Candida Diet: A potent therapeutic adjunct to the treatment of candidiasis is an anti-candida diet. The anti-candida diet focuses on the elimination of sugars that can contribute to yeast overgrowth thus promoting the ability of candida to adhere to epithelial mucosal cells. This includes sweetened drinks, sodas, fruit drinks, fruits, corn syrup, and other high sugar content products. Other dietary recommendations include the reduction of dairy products, breads, pastas and foods high in yeast (such as cheese, peanuts, and alcohol). Table 1 outlines food choices traditionally used in addressing CRC and candidiasis.

Table 1 Anti-Candida Diet Choices and Exclusions

Food Choices to address Candida




Snow Peas








































Brussels Sprouts

String Beans


















Nuts and Seeds (moderation)

Grains (lesser amounts)






Pine nuts












Brown Rice






Oils (cold Pressed)






Foods to Avoid


Fruit Juices




Dried Fruit



Sugar – all forms

Refined Flours

Baked Goods

Pickled vegetables


Garlic: Garlic has a long tradition of use as an antimicrobial, demonstrating its ability as a viable anti-infective agent. Garlic is the common culinary name for the herb allium sativa, which is related to the common onion, allium cepa. In fact, all herbs of the genus allium possess anti-candidal properties. The major constituents contributing to its anti-fungal effect are allicin and other related breakdown products. Allicin is a molecule that is converted from alliin by enzymes activated when garlic is damaged. These enzymes are deactivated when exposed to gastric acid and heat, thus cooking will reduce the effectiveness of garlic. The whole fresh herb extract of garlic has been shown to be more effective than doses of the dried herb, possibly due to the relative instability of the allicin molecule. The extensive research into garlic concludes that it is a clinically effective treatment for infectious diseases including bacterial and fungal pathogens. The clinical application of garlic includes digestive, respiratory, vaginal, and dermatological infections. Adverse reactions are few, however high doses of garlic may result in breath and body odour, mouth and gastrointestinal burning, irritation, heartburn, flatulence, nausea, vomiting, and diarrhea. Topical application of garlic may induce dermatitis especially if applied for prolonged periods.

Pau d’arco: Preparations of pau d’arco are derived from various species of the tabebuia tree. Traditionally a decoction of pau d’arco was used as a douche for the treatment of vaginal conditions. Current research has revealed that the herb possesses anti-inflammatory, immune modulatory and stimulatory properties. The proposed antimicrobial action may be due to the ability of pau d’arco constituents to inhibit the uptake of oxygen by the affected cells, inhibiting the main respiration pathway. This characteristic, in addition to its immunomodulating ability, is considered to be chiefly responsible for its anti-candida effect. Adverse reactions only occur at high doses and may present as severe nausea, vomiting, diarrhea, dizziness, anemia, and an increased risk of bleeding.

Echinacea: Echinacea has been recognized for its beneficial effect on the immune system, particularly towards infectious disease. Studies examining the effectiveness of echinacea in regards to infectious disease have shown that it possesses anti-microbial activity in addition to immune modulatory effects. In general echinacea is well tolerated, however possible adverse reactions may include: allergic reactions, fever, nausea, vomiting, abdominal pain, diarrhea, sore throat and dizziness. People who have a history of atopic reactions or allergic reactions to the ragweed family may react with echinacea therefore caution is recommended.

Goldenseal/Oregon Grape Root/Barberry: These herbs share common constituents, namely berberine and other related alkaloids, which serve as powerful antimicrobial agents. The use of berberine has been repeatedly shown to be an effective treatment for numerous microbial infections including candida.  Clinical research has concluded that herbs containing berberine offer a potentially effective treatment for numerous resistant strains of microorganisms and have been studied as adjuncts to current antibiotic therapies. Prolonged use of goldenseal may result in digestive disorders, constipation, excitatory states, and occasional delirium. Oregon grape has no associated adverse effects except if taken at very high doses (due to the berberine), which may cause lethargy, nosebleeds, skin and eye irritation, kidney irritation, dyspnea, hypotension, cardiac damage, nausea, vomiting, diarrhea, respiratory spasms, and potentially death. Topically Oregon grape may cause itching, burning, skin irritation, and allergic reactions.

Tea Tree: The oil derived from the tree melaleuca alternifolia has a long history of use as an anti-microbial effective against various strains of bacteria and fungi. Numerous studies have examined the properties of tea tree in relation to skin infections particularly athlete’s foot, ringworm (another common fungal infection) and nail infections. In all cases the oil was determined to be a clinically effective treatment for these conditions resulting in remarkable improvement or complete recovery.  Additional studies have examined the use of tea tree in the treatment of oral and vaginal candidiasis. The results of these studies conclude that tea tree oil is an effective treatment of both oral and vaginal candidiasis including fluconazole (a common drug used in the treatment of candida infections) resistant candidiasis. Adverse reactions may occur if administered orally, resulting in confusion, inability to walk, disorientation, ataxia, and systemic contact dermatitis. Topical application is well-tolerated but may cause irritation and inflammation, allergic contact eczema, and allergic contact dermatitis.

Oregano oil: Oil of oregano is derived from oregano vulgare, which should not be confused with common oregano (oregano marjoram) often used as a culinary herb. Oregano oil contains the active constituents carvacrol and thymol, which have clinically significant antifungal properties. These active ingredients also exhibit antibacterial properties by inhibiting the growth of common bacterial pathogens such as E. coli and Salmonella species. In one study, oregano oil was compared to a common antibiotic, amphotericin B, and was found to be just as effective in the treatment of candidiasis. Other studies have indicated its beneficial use for mucocutaneous candidal infections, including oral thrush.  Enterically coated oregano oil will protect the oil and ensure that it is delivered into the intestines instead of being absorbed by the stomach where it can induce heartburn. This also ensures that the antifungal activity is directed where needed by delivering the oil further down in the gastrointestinal tract. Oregano oil has few adverse reactions associated with its use. Large oral doses of oregano oil may cause gastrointestinal upset and possibly cause systemic allergic reactions.


Probiotic: A Probiotic is a mix of several non-pathogenic microorganisms, typically including Lactobacillus andBifidobacterium, which are beneficial microorganisms found in the gastrointestinal system. They act by populating the digestive system, thus preventing adhesion by other microorganisms and subsequently releasing inhibitory agents against known disease-causing bacteria, viruses and fungi. Numerous studies have examined the impact of probiotics on candidal infections, particularly vaginal and oral infections. These reports indicate a reduction in the frequency and duration of infections, a reduction in colonization levels, a decrease in severity and progression of infections, and the capacity to eliminate current vaginal infections using a douche containing acidophilus cultures. The scientific research confirms the clinical importance of probiotic use with oral, gastrointestinal and vaginal candida-related infections. Very few adverse effects have been reported from the use of probiotics but may include flatulence and constipation. They are generally well tolerated.

Caprylic Acid: Is a medium chain 8-carbon fatty acid derived from coconut oil and has been traditionally used to treat fungal infections. It has been reported to have antifungal activity in vitro studies. However, clinical research into its efficacy has been limited with few studies examining its antifungal properties. One small study indicated that the use of caprylic acid may reduce the subjective symptoms of candidal overgrowth, supported by objective findings of reduced stool candida culture levels. Other studies have reported the successful treatment of both intestinal candidiasis (via a caprylic acid complex) and the elimination of progressive thrush infections. Due to its fat-solubility, it is best taken with fatty foods to optimize intestinal absorption. Caprylic acid may generate mild gastrointestinal symptoms such as nausea and diarrhea and has been associated with an unpleasant taste if consumed in an unencapsulated form.

Undecylenic acid: Is an 11-carbon fatty acid derived from the distillation of castor bean oil. The antifungal properties of undecylenic acid are attributed to its ability to disrupt the pH of cells, interfere with fatty acid biosynthesis and inhibit the conversion of the yeast to its active hyphal form. It demonstrates potent fungicidal effects, up to ten times more effective than caprylic acid. Studies have indicated that it is an effective treatment for vaginal and gastrointestinal candidiasis, while maintaining a healthy balance of normal flora. Oral doses are absorbed and dispersed systemically and are thus capable of addressing both internal and external candidal infections. Clinical reports support the use of undecylenic acid for the prevention and treatment of thrush and denture induced candidal stomatitis. Topical preparations have shown remarkable reduction in skin infection rates and symptoms without adverse reactions or side effects. Both oral and topical dosages that are effective in the treatment of candidiasis appear to be safe. Undecylenic acid may be irritating to mucus membranes and has an objectionable taste and smell, therefore it is encapsulated to eliminate these effects. The undiluted oil may cause skin irritation when applied directly to the skin thus it is necessary to dilute it in an appropriate oil before applying topically.

Olive leaf extract: Extracts from the common olive leaf (olea europaea) have shown antimicrobial potential. Research has demonstrated that the extract is effective against numerous bacteria and fungi, including C. albicans. However, more research is needed to further elucidate the effectiveness of olive leaf compared to other anti-fungal agents and its overall therapeutic benefit in candidal infections. Olive leaf has been established as a potent anti-viral with antibacterial properties. It has been used without any noticeable side effects and is generally considered safe with no reported adverse reactions in the scientific literature.

Table 2 Summary of Candidiasis diagnosis, predisposing factors and treatment


Disposing Factors




Mouth Antibiotic Use Garlic Probiotic
Nails Pregnancy Tea tree Caprylic Acid
Vagina Hot Weather Pau d’Arco Olive Leaf Extract
SkinSkin Folds Restrictive Clothing Oregano Oil Undecylenic Acid
Gastro-intestinal Corticosteriod Use Oregon Grape Root
Systemic Birth Control Pills GoldensealBarberry


1.        Tierney, J M, McPhee, S J, Papadakis, M A. Current Medical Diagnosis and Treatment, 42nd edition. McGraw Hill Companies Inc. Toronto, Canada, 2003.

2.        Hammer KACarson CFRiley TV.Antimicrobial activity of essential oils and other plant extracts. Oral Microbiology and Immunology. Volume 20 Page 106  – April 2005

3.        Braunwald E, Hauser S L, Fauci A S, Longo D L, Kasper D L, Jameson J L. Harrison’s Principles of Internal Medicine 15th Edition. The McGraw-Hill Companies, Inc. Toronto, Canada, 2001.

4.        Undecylenic Acid Monograph. Alternative Medicine Review, Volume 7, Number 1, 2002. Thorne Research Inc., 2002.

5.        The Merck Manual

6.        Z. M. Ross, E. A. O’Gara, D. J. Hill, H. V. Sleightholme, and D. J. Maslin. Antimicrobial Properties of Garlic Oil against Human Enteric Bacteria: Evaluation of Methodologies and Comparisons with Garlic Oil Sulfides and Garlic Powder St. George’s University, St. George’s, Grenada, West Indies, and University of Wolverhampton, and West Midlands Regional Genetics Service, Birmingham Women’s Hospital, Birmingham United Kingdom. November 2000

7.        Ellen Tattelman, M.D Health Effects of Garlic. Albert Einstein College of Medicine of Yeshiva University, Bronx, New York

8.        Nakamoto KSadamori SHamada T Effects of crude drugs and berberine hydrochloride on the activities of fungi. [J Prosthet Dent 1990 Dec; Vol. 64 (6), pp. 691-4

9.        Iwalokun BAOgunledun AOgbolu DOBamiro SBJimi-Omojola JIn Vitro Antimicrobial Properties of Aqueous Garlic Extract Against Multidrug-Resistant Bacteria and Candida Species from Nigeria:JOURNAL OF MEDICINAL FOOD, Sep 1, 2004; 7(3): 327-33

10.     Park KSKang KCKim JHAdams DJJohng TNPaik YK. Differential inhibitory effects of protoberberines on sterol and chitin biosyntheses in Candida albicans. J Antimicrob Chemother 1999 May; Vol. 43 (5), pp. 667-74

11.     Cox SDMann CMMarkham JLBell HCGustafson JEWarmington JRWyllie SG The mode of antimicrobial action of the essential oil of Melaleuca alternifolia (tea tree oil). J Appl Microbiol] 2000 Jan; Vol. 88 (1), pp. 170-5.

12.     Nakamoto KSadamori SHamada T Effects of crude drugs and berberine hydrochloride on the activities of fungi J Prosthet Dent] 1990 Dec; Vol. 64 (6), pp. 691-4

13.     Wilkinson JMCavanagh HM. Antibacterial activity of essential oils from Australian native plants. Phytother Res 2005 Jul; Vol. 19 (7), pp. 643-6

14.     Mondello FDe Bernardis FGirolamo ASalvatore GCassone A. In vitro and in vivo activity of tea tree oil against azole-susceptible and -resistant human pathogenic yeasts. J Antimicrob Chemother 2003 May; Vol. 51 (5), pp. 1223-9

15.     Slobodníková LKost’álová DLabudová DKotulová DKettmann V Antimicrobial activity of Mahonia aquifolium crude extract and its major isolated alkaloids. Phytother Res 2004 Aug; Vol. 18 (8), pp. 674-6.

16.     Ridley, Vicky Pau d’arco (Tabebuia spp.) British Journal of Phytotherapy, 09596879, 2001, Vol. 5, Issue 3

17.     Pau D’Arco: Antifungal Activity of Active Constituents Quarterly Review of Natural Medicine, 1082541X, Spring95

18.     Han YLee JH Berberine synergy with amphotericin B against disseminated candidiasis in mice. Biol Pharm Bull 2005 Mar; Vol. 28 (3), pp. 541-4

19.     Chretien JHEsswein JGSharpe LMKiely JJLyddon FE. Efficacy of undecylenic acid-zinc undecylenate powder in culture positive tinea pedis. Int J Dermatol 1980 Jan-Feb; Vol. 19 (1), pp. 51-4.

20.     N. Chami1, S. Bennis1, F. Chami1, A. Aboussekhra2, A. Remmal.  Study of anticandidal activity of carvacrol and eugenol in vitro and in vivo Oral Microbiol Immunol 2005: 20: 106-111

21.     Markin DDuek LBerdicevsky I. In vitro antimicrobial activity of olive leaves. Mycoses 2003 Apr; Vol. 46 (3-4), pp. 132-6.

22. accessed 24/10/2006 Oct. 21, 2006

23. Oct. 21, 2006

24.  accessed Oct. 21, 2006.