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Some clinicians believe that autistic symptoms are made worse by the overgrowth of Candida albicans, a yeast-like fungus present everywhere, and will prescribe anti-fungals. For mild cases of yeast over-growth, diet along with a healthier lifestyle may resolve the problem. However, in moderate to severe problems, an anti-fungal drug or a natural product with anti-fungal activity may be needed. The question of whether to use a drug or a natural product is one for you and your doctor to decide upon.

Anecdotal reports and the limited scientific evidence that is available suggest a lot of the natural products seem to be as effective as many of the anti-fungal drugs. The exception to this is the systemic drugs, which are reserved for difficult cases in which the child doesn’t respond to either drugs that only act in the intestine, such as Nystatin, or to natural anti-fungals. Most doctors treating yeast overgrowth suggest patients will need to take the majority of anti-fungals for at least 3 months and some will have to stay on them indefinitely. Of course, most will be somewhere in between these extremes.

With anti-fungal treatment, there is a chance of experiencing what is known as the Herxheimer or “die-off” reaction. This is said to occur as a result of the yeast being killed too rapidly, which overwhelms the body with yeast cells and their toxins. Any number of nasty symptoms can arise as a result, most frequently a flu-like feeling or worsening of symptoms already present. The solution to this may be to take a lower dose of anti-fungal for a while, or take extra fibre or a product like bentonite clay to help carry the toxins out of the body before they are absorbed.

Anti-Fungal Medications

Nystatin was one of the first anti-fungal drugs developed and probably the most commonly used to treat intestinal yeast overgrowth. It is extremely safe due to the fact that hardly any of the drug is absorbed from the intestinal tract. As a result, the only side-effects that may occur are mainly restricted to the digestive system and are usually mild. In addition, in rare cases patients may develop a rash as a result of an allergic reaction. Nystatin is available in a number of different forms, including tablets, powder and liquid oral suspension. You can therefore choose the form that suits you best. The liquid and powder forms are probably superior to tablets because they don’t need to be digested before they start to work and hence will kill yeast further up the digestive tract. The only drawback to this is the extremely foul taste!

Amphotericin B is similar to nystatin as it is chemically related. As with nystatin, it is not absorbed from the intestine in any significant amount, so again is very safe. You may hear stories of amphotericin being very toxic or poisonous; but this is most likely referring to IV use of the drug in hospitalized patients suffering a fungal infection of the blood or severe infection of body tissues. This doesn’t apply to its use in the digestive tract. Amphotericin B may be effective in cases where nystatin has failed, so it is something to consider if that is the case with you.

Diflucan belongs to a group of drugs called the ‘azoles’ and, unlike the previous two drugs, Diflucan is absorbed by the intestines and is referred to as a systemic anti-fungal drug. Diflucan is a more modern drug than nystatin and amphotericin. It was first used in Europe during the 1980’s and licensed in the US in 1990. A lot of doctors and patients have found Diflucan (and other azoles) to be effective where nystatin and amphotericin have failed. It has been found to be very safe, considering its systemic action, with few side-effects reported by patients.

Sporanox is one of the newest azole drugs, having been licensed in the US in 1993. It would seem to be similar to Diflucan in safety and effectiveness, but may be a more successful treatment for certain species of Candida and other fungal infections as Diflucan may be more effective for other species. Unless you have a stool sample tested and a particular species of Candida/yeast can be detected and tested for sensitivity to different drugs, it is a matter of trial and error with regard to which will work best for you.

Nizoral (ketoconazole) was the first of the azole drugs to be developed, but its use is limited due to the possibility of serious liver damage. As a result, patients must undergo regular liver enzyme tests during treatment to monitor the effects. In cases that have failed to respond to any other anti-fungal agent its use may be justified, but otherwise, it is probably best avoided.

Lamisil (Terbinafine HCL) is the newest anti-fungal drug in routine use. It is a systemic drug but is unrelated to the other systemic ‘azole’ drugs. As a result, it is an effective treatment, as yeast has not yet had the chance to develop resistance to it. Lamisil has become more and more widely used since its introduction a few years ago and is set to become the systemic drug of choice, replacing Diflucan. As with most of the systemic drugs, there have been instances of adverse effects on the liver, and as with Sporanox, Lamisil has recently been linked with congestive heart failure.

Natural Anti-Fungals

Saturated Fatty Acids, such as undecylenic and caprylic acids, are common medium chain saturated fatty acids used to treat yeast infections. Both are found naturally in the human body in small amounts. Common commercial sources of caprylic acid are palm and coconut oils, whereas undecylenic acid is extracted from castor bean oil. Caprylic acid products are far more common than those of undecylenic acid, but don’t assume this means it is better; undecylenic acid has far more research data available on it and was the treatment of choice for fungal skin infections for a long time before newer drugs arrived.

Berberine is an alkaloid found in an herb called barberry (Berberis vulgaris) and related plants as well as in goldenseal, oregon grape root and Chinese goldthread. This herb has long been used in chinese and ayurvedic medicine. Berberine has significant anti-fungal activity and is also effective against some kinds of bacteria. As with all previously covered anti-fungals, berberine is reported to spare beneficial organisms such as lactobacilli species. An added benefit for some people is its anti-diarrheal action. Research has shown that berberine can effectively prevent Candida species from producing an enzyme called lipase, which they use to help colonize. Berberine has also been widely shown to have a powerful directly anti-fungal action.

Oregano is familiar to most people as the strong smelling herb commonly used as a seasoning in Italian food. This is usually Oregano marjoram rather than Oregano vulgare which we are interested in here. Oregano vulgare contains a variety of substances that make it an effective anti-fungal. In a study assessing its action against Candida albicans, carvacrol, a major phenolic constituent of the oil Oregano vulgare, was found to inhibit Candida to a greater extent than caprylic acid. It is also highly effective against many bacteria with studies published in the most prestigious medical journals showing it to be as effective as many antibiotic drugs.

Garlic (Allium sativum) contains a large number of sulphur-containing compounds that exhibit potent anti-fungal properties. Among the most studied are allicin, alliin, alliinase and S-allylcysteine. Some studies have found garlic to be at least as effective as nystatin at killing Candida albicans. A point that should not be overlooked is that, because of the many different compounds with anti-fungal properties in garlic, yeast and fungi are unlikely to become resistant to it. Garlic also has many other beneficial properties, particularly for the cardiovascular system. For treating intestinal yeast infections, garlic is available in a number of different forms, including odourless capsules, liquid extract and tablets. However, a study at the National Institutes of Health found that fresh garlic was significantly more potent against Candida albicans. It also found that the fresh garlic could be a suitable alternative to drugs for serious systemic infections in patients with severe immune suppression. Therefore, adding garlic to food (raw), or crushing and swallowing raw cloves if you can tolerate it, is a cheap and powerful anti-fungal treatment.

Colloidal Silver is a suspension of silver particles in water (note: colloid is defined as very small particles of one substance suspended – not dissolved – in another) . Silver is a well known anti-microbial. It is commonly used in items such as water filters to kill any microbe that may be in the water, including bacteria, fungi, worms and protozoa. Colloidal silver is said to be effective against up to 650 pathogens, including yeast and fungi species (including Candida). It works by denaturing the enzyme involved with supplying the organism with oxygen. Chances of resistance to this process are by all accounts very low. It was used widely to treat infection before the development of antibiotic drugs. It is now classified as a pre-1938 drug by the FDA, which means that it is available without prescription. The number of companies offering colloidal silver as an alternative to antibiotic medications is increasing daily. The renewed interest can be explained by the increase in chronic infections and the fact that many microbes are becoming resistant to commonly used drug treatments.

Cellulase is a relatively new treatment approach for intestinal yeast infections. The cell wall of common intestinal yeast such as Candida species has been found to be made mainly from cellulose. Cellulase is the enzyme that breaks down cellulose and hence, when significant concentrations come into contact with yeast cells the cell wall is irreparably damaged and the organism dies. It’s claimed that using this mode of action, the yeast do not release a flood of toxins when they die as occurs with most other anti-fungal agents. This way the sufferer does not experience the usual die-off symptoms to any significant degree. The yeast should be unable to develop resistance to cellulase products as they lack the ability to modify their cell wall. As cellulase products have only been around for a few years, reports of their effectiveness in practice are limited, although they offer a promising alternative to more established treatments.

Plant Tannins are natural substances found in a number of plants, such as Black Walnut and a vast array of plants used in traditional eastern medicine. Tannins are what give red wines such as merlots and cabernets their sharp, biting taste. They are also found in the bark of trees that are particularly resistant to fungus, such as the redwood tree. They have been demonstrated to have a powerful anti-fungal and astringent action in a multitude of clinical studies. Tannins are one of a number of natural substances tested against pathogens found in stool samples by functional medicine labs. Tannins are available in a number of forms, both isolated and concentrated, to treat intestinal yeast overgrowth.


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