Candida-Related Complex(CRC) FAQ

Candida-Related Complex(CRC) FAQ

What is CRC/chronic candida?

Chronic candida refers to a cluster of systemic and gastrointestinal symptoms that some physicians report responds to anti-candida treatment. Nationwide, there are at least 300 MDs who recognize and treat the condition2. There is no reliable information on it's incidence, cause, or effective treatment because there has been very little research. The only focused study was one done in 2001 that seems to confirm the condition exists1. Many patients demand treatment despite the lack of research because the treatment is empirically effective and the conventional approach to their illness failed (this often consists of simply dismissing the patient's complaints as stress or somatization disorder).


In 1983, Dr. C. Orian Truss published "the Missing Diagnosis"2, a treatise on his success treating what were thought to be psychosomatic symptoms with anti-candida measures. William Crook published "The Yeast Connection"3 the same year, in which he reported similar positive results.

Other practitioners have tried these measures and reported the same positive results. The pattern of symptoms in these patients were referred to as "chronic candida", but have recently also been labeled Candida-Related Complex(CRC).

The cardinal symptoms of CRC usually include the following:

Gastrointestinal: Systemic: Mental/emotional:
Indigestion, bloating
Food intolerances
Weight loss
"brain fog"

Because the condition responds to anti-candida antifungals, it is presumed to be caused by gastrointestinal candida overgrowth. This is recognized as a side-effect of antibiotic use, which patients often link to the onset of their symptoms. The severity of symptoms and their response to treatment is variable. Some patients report a complete recovery. Those who have been sick longer may report improvement, but remain unwell.

How is it diagnosed?

There are some tests believed to be useful for diagnosing CRC4, but none are scientifically proven to identify the condition. MDs may make a diagnosis based on the pattern of symptoms listed above, after ruling out other possible causes (i.e. hypothyroidism, clinical depression, hypoadrenalism, celiac sprue, food alergies, etc). The symptoms should improve with one or more anti-candida antifungals and dietary changes(such as the elimination of sugar). A history of repeatedly or extended exposure to antibiotics prior to developing symptoms supports the diagnosis.

How is it treated?

There is only one study showing effective against the cluster of symptoms referred to as CRC1. Below is a summary of what practitioners have reported as effective in the various books on the subject.

Doctors who recognize CRC vary in how they treat it, based on their own experience. Many or most use prescription antifungals, such as nystatin, diflucan, and sporanox. Most practitioners (and books on chronic candida) advise dietary changes as a cornerstone of treatment. The most common recommendation is the elimination of sugar from the diet. An exacerbation of symptoms after eating sweets is a cardinal symptom of the condition. The elimination of "junk-foods" (i.e. potato chips) is also often advised. Other dietary suggestions differ depending on the source.

If antifungals and abstaining from sugar fail to improve one's symptoms, I personally don't consider them to be caused by chronic candida. Since there is not definitive test that proves someone has it or not, this is the guide I go by. Others may use a different standard.

If you have found a treatment that works for you, please share your results with others by entering a profile in this site's patient database, so others may benefit.

What is the controversy?

New medical therapies are normally researched, written up in the medical literature, and officially recommended by medical societies before they are considered acceptable for use by a physician's patients. There is no regulatory process for new medical treatments, so doctors can legally treat chronic candida. However, they are required by local medical boards to "conform to the prevailing standard", for better or for worse. That means if you have an effective treatment for those with chronic candida, and it's not accepted by other physicians, you could be accusing of failing to conform to the prevailing standard, regardless of how much your patients improve. Some doctors have provided anti-candida treatment despite the limited research done because it's the only thing that works for their patients.

Some alternative/complimentary practitioners(naturopaths, chiropractors, herbalists, acupuncturists) promote their services for the treatment of chronic candida. Supplement makers have also marketed several products to relieve yeast or candida problems.

What needs to be done?

Epidemiological research that defines the syndrome scientifically must be done. Clinical research need to test the various treatments purported to be effective against it. In the absence of such research, medical authorities have either ignored the disease or denounced it. The routine approach to patients with the clinical picture of CRC is to label their symptoms as functional or psychosomatic. They are not investigated further because they don't constitute a known medical condition.

Finding a doctor

I do not have a list of physicians who are willing to treat chronic candida. Various lists have been compiled by the International Health Foundation(an organization Dr.Crook founded), CDIF, and in the back of some books on this problem. These lists are not necessarily current. You may want to search for a doctor who is listed with the American College of Advancement in Medicine:

A list is published in the back of the book "Candida-Related Complex, What Your Doctor Might Be Missing", by Christine Winderlin and Keith Sehnert MD, Taylor Publishing Co, 1996(ISBN: 0878339353)

The psychosomatic label

Many patients who are diagnosed with CRC are considered by mainstream practitioners to suffer from somatization disorder. CRC patients usually lack the number and extent of symptoms necessary to be diagnosed with that disorder5. CRC is purportedly diagnosed only when there is a favorable and lasting response to anti-Candida treatment. This suggests a physical rather than psychological basis for their symptoms. This issue will remain unresolved until CRC is formally studied, and the value of anti-candida treatment can be substantiated.

Dysbiosis, a similar label

Some practitioners refer to both Small Bowel Bacterial Overgrowth(SBBO) and CRC collectively as "dysbiosis". Both conditions are initiated by a disruption of the normal gastrointestinal microflora. The symptoms of dysbiosis are attributed to "leaky gut", or an increase in intestinal permeability that allows antigens from the GI tract to reach the bloodstream. This has some support in recent medical literature on mucosal immunity and intestinal permeability. Additional research in the area of intestinal permeability may begin to answer the question of what is causing the symptoms seen in CRC/chronic candida patients. Better interventions could then be sought, such as probiotics that reverse this particular pathology. A second promising line of research is the effort to understand candida pathogenicity at places like the University of Minnesota. Their recent discovery of a key gene in Candida's pathogenic potential may lead to more effective antifungal drugs.

Some believe the fatigue and other symptoms seen in CRC are caused by disordered intestinal permeability, which allows intact antigens to pass through the GI mucosa. Disordered intestinal permeability

Scientific support

There is scientific support for some features of the CRC hypotheses. Antibiotics are known to promote GI candida overgrowth, and even penetration of the GI mucosa6. Elimination of sugar from the diet of mice can improve the outcome of a Candida infection7. The mechanism for symptoms such as fatigue and "brain fog" in CRC patients is more of a mystery. However, the same symptoms are common to SBBO. At least one clinical trial supports the CRC syndrom1.


  1. Santelmann H, "Effectiveness of nystatin in polysymptomatic patients. A randomized, double-blind trial with nystatin versus placebo in general practice." Fam Pract. 2001 Jun; 18(3):258-65.
  2. Candida-Related Complex, What Your Doctor Might Be Missing, by by Christine Winderlin(with Keith Sehnert), Taylor Publishing Co, 1996 ISBN 087833-935-3
  3. The Missing Diagnosis, by C. Orian Truss, The Missing Diagnosis Inc, 1983
  4. The Yeast Connection, by William Crook, MD, Random House Inc, 1983
  5. Cater RE II "Somatization disorder and the chronic candidiasis syndrome: a possible overlap" Medical Hypotheses (35):126-135, 1991
  6. Kennedy, MJ et al. "Mechanisms of association of Candida albicans with intestinal mucosa" Med Microbiol 24:333-341, 1987
  7. Vargas SL et al "Modulating effect of dietary carbohydrate supplementation on Candida albicans colonization and invasion in a neutropenic mouse model" Infection and Immunity 61(2):619-626, Feb. 1993

This page last modified 2023-04-30