Introduction to helminthic therapy
What is helminthic therapy?
Helminthic therapy is the reintroduction to the digestive tract of a controlled number of specially domesticated, safe, mutualistic helminths (intestinal worms) in the form of microscopic eggs or larvae to treat and prevent disease.
The organisms that are used are similar to the ones with which people living in developed countries have gradually lost contact during the past 150 years as a result of the widespread use of flush toilets, refrigerators, food storage technologies and food preservation techniques.
Viewed from a medical perspective, helminthic therapy can be seen as an experimental form of immunotherapy that is being trialled to a limited extent as a treatment for chronic inflammation, autoimmune disease and other immunological disorders including allergy.
It is also used by many thousands of individuals as a form of probiotic self-treatment, employing tiny animals instead of bacteria to improve health by reconstituting and enriching a depleted intestinal biome.
This practice is known variously by the following terms:
- Helminthic therapy
- Helminth therapy
- Helminth replacement therapy
- Helminth-induced immunomodulation therapy (HINT) 
- Worm therapy
- Biome restoration
- Biome reconstitution
Visitors who are using a desktop computer will find that hovering their cursor over unknown words and abbreviations will often reveal a feint underlining. Clicking on those words will bring up a definition. Alternatively, go to the Terminology page.
A brief history of helminthic therapy
Following the first appearance, in 1968, of evidence pointing to the importance of helminths for human health,  further evidence emerged in the 1970s, including a report of higher levels of allergic disease in urban communities than in rural indigenous areas where levels of helminth colonisation were much higher. 
By 1990, it had become clear from further scientific studies that, while autoimmune, inflammatory and allergic conditions had escalated in developed countries during the twentieth century, they had remained much less common in parts of the world where helminths are still prevalent. (See this distribution graphic prepared by the late Prof Robert Summers, circa 2000.) It was this realisation that gave rise to the idea of reintroducing helminths into patients who have developed these conditions, in the hope that this intervention might rebalance their immune system and restore their health. The first indication that this might be an effective approach had already appeared in the Lancet in 1976, when a researcher had reported putting his own seasonal allergies into remission by infecting himself with hookworms. 
Researchers began to consider the importance to health of what has become known as the microbiome, and the theories formed by these pioneers have been refined through several stages, each being given a new title, viz. the Hygiene Hypothesis, the Old Friends' Hypothesis and, most recently, Evolutionary Mismatch Theory and Biome Depletion Theory/ Biota Alteration Theory.
During this process, helminths were identified as being of special significance, and they are now considered to be keystone species of the human multibiome, with profound importance for health. So much so that there are calls for them to be employed not only as a treatment for established disease, but also as a preventative to help eliminate the pandemics of allergic, inflammatory and autoimmune diseases that are today afflicting the populations of developed countries, and possibly also to offer protection against many degenerative diseases such as atherosclerosis, diabetes and cancer.
Most members of the medical profession remain sceptical about the use of live helminths, while some are overtly hostile, and none will be able to use these organisms in medical practice until validated in each target disease by clinical trials.
Unfortunately, where helminths have been the subject of studies, these have often employed methods that were designed to test pharmaceutical products and are unsuitable for the assessment of a natural therapeutic, especially one whose beneficial effects do not become consistent for at least twelve weeks - the typical limit of drug trials - and, in a few cases, have taken as long as two years to materialise. Unsurprisingly, some of these trials have failed to show efficacy, in contrast to the experience being reported by many thousands of individuals who are self-treating with helminths.
As a consequence of the current medical approach, millions of patients are being forced to continue to suffer the often devastating effects of immunological disorders, along with the frequently serious side effects produced by many of the pharmaceutical therapies currently prescribed to treat them. And this is in spite of the fact that four helminth species have already been identified as suitable and safe for use in therapy and are currently being used successfully for self-treatment by many thousands of individuals.
Several of the researchers who have examined the effects of helminths on autoimmune disease admit privately that, were they or a member of their family to succumb to an autoimmune disease, they would not hesitate to use one of the available therapeutic helminths. A few have even said this publicly.
While citizen scientists continue to refine the therapeutic use of live helminths, the vast majority of medical researchers have their sights set on the creation of drugs employing helminth-derived molecules. However, some researchers have suggested that no worm-derived pharmaceutical will ever match the efficacy of a live worm.
Helminth-derived pharmaceutical products are still many years away, and if and when they do become available, some, if not all of them, are likely to present adverse side effects, as are seen frequently with other single molecule drugs. In contrast, none of the living helminths that are currently in use therapeutically causes long-term side effects.
The use of live worms could greatly reduce the cost of medical treatment.
Acceptance of helminthic therapy by the medical establishment is currently hindered by the strong pharmaceutical bias of modern Western medicine, and by an inflexible medical research system that ignores vibrant sources of new knowledge generated by activist patients such as those who have contributed to this wiki and its associated groups and blogs. 
However, in spite of these factors impeding acceptance, helminthic therapy is nevertheless predicted to become an essential part of healthcare in the future.
Helminthic therapy science
Here is a short selection of scientific papers that provide a good overview of the therapeutic potential of controlled colonisation by benign helminths.
For a full list of scientific papers and articles from the media documenting the history and development of helminthic therapy from its beginnings up until the present day, see the following pages.
Helminthic therapy safety
Helminthic therapy is very safe. For details, see the following page.
- should not cause disease in humans at therapeutic doses
- should not be a potential vector for other parasites, viruses, or bacteria
- should not cause long-term symptoms in humans at therapeutic doses
- should not alter its behaviour in patients with depressed immunity
- should not be easily transmissible from the host to other people
- should not be able to reproduce in a host, and thus prevent dosage from being controlled
- should be easily eradicated from the host, if required
- should be compatible with commonly used medications
- should be easy to administer
- should be amenable to production in large numbers
- should be amenable to storage and transportation
There are currently four types of helminth available commercially for use in self-treatment. All of these meet the above criteria.
- Pig whipworm, Trichuris suis (TS)
Introduced for therapy in 2003. Sold as ova (TSO) and taken as a drink.
- Human hookworm, Necator americanus (NA)
Introduced for therapy in 2006. Sold as microscopic larvae which are applied to the skin.
- Human whipworm, Trichuris trichiura (TT)
Introduced for therapy in 2009. Sold as ova (TTO) and taken in a drink.
- Rat tapeworm, Hymenolepis diminuta (HD)
Introduced for therapy in 2011. Sold as cysticercoids (HDC) and taken in a drink.
Choosing a therapeutic helminth
See the separate page:
Helminthic therapy in practice
Helminthic therapy is contraindicated for people with certain conditions.
Some conditions require a much more gradual approach to dosing.
The guidelines offered on this site for the therapeutic use of NA, HDC, TTO and TSO are essential reading for anyone considering self-treatment with these species.
Self-treatment with helminths is very individual so, even with guidance, it can take a while to establish the ideal dosing regimen.
Helminthic therapy is typically very slow to deliver benefits when compared with drugs. For the majority who do respond, significant and consistent improvements do not usually materialise until at least 3 months after the first inoculation, with most people only seeing improvement in their condition between 3 and 5 months. Some may only start to improve between 6 and 12 months and a few may even have to wait for as long as 18-24 months.
Once improvements do begin to materialise, some people can experience a sudden and dramatic reduction in symptoms, while others may respond more gradually over a period of time, possibly three years or more. Improvements during the first 2 years are not always continuous because there can be periods of exacerbation during which symptoms may worsen again, albeit temporarily. And approximately 25% of those who try helminthic therapy do not respond at all.
Helminthic therapy is also not a one-size-fits-all solution, nor a one dose fix. Dosing needs to be tailored to the unique needs of each individual, and continued indefinitely in the vast majority of cases.
It is not yet possible to predict exactly who is likely to benefit from helminthic therapy, but statistics compiled from responses to a survey carried out by one provider of NA showed that 70-80% of those who self-treated with this species experienced an improvement in their health.  The report of a survey conducted by researchers at Duke University showed that treatment with HDC was effective in more than 90% of cases, although this apparently higher efficacy of HDC in comparison with NA is likely to be at least partly due to the fact that users of HDC tend to be relatively less ill than those who use other therapeutic helminths.
Helminthic therapy is not always a complete solution on its own, and some self-treaters need to combine this therapy with other treatments, either complementary or pharmaceutical. For example, one self-treater has said:
There are many examples of both successful and unsuccessful outcomes in the Helminthic therapy personal stories collection, which presents thumbnails and links to more than 600 accounts by people who have used helminthic therapy to treat over 130 different medical conditions.
Since this therapy is still at the experimental stage, there are not yet any definitive guidelines for its use and there are very few doctors who understand helminthic therapy, let alone have any practical experience with it. A few medics are using HDC in some client groups, especially children with autism (video) and a few doctors may recommend that patients with various autoimmune conditions try TSO. There is also a small but growing number of doctors, especially naturopathic practitioners, who are recommending the use of NA and a few doctors have become sufficiently knowledgeable to be able to advise self-treaters. (See Helminthic therapy practitioners.)
The helminth providers are another valuable source of information and guidance, although no one company sells or has experience with all four helminth species, so they are unlikely to be able to match the objectivity or breadth of information found in this wiki, which offers a balanced assessment of all 4 available helminth species based on the findings of science and the first-hand experience of self-treaters. It is therefore recommended that, before proceeding with this therapy, each would-be helminth self-treater should make full use of this site and familiarise themselves with as much of its contents as possible.
Newcomers to helminthic therapy will often ask in the support group for personal recommendations about the best place to buy helminths, but purchasing worms for therapy needs to be approached on an individual basis.
There are four different species of therapeutic helminth available with two different methods of application, widely differing lifespans and somewhat different effects. None of the companies who supply therapeutic helminths sell all the available species, ship to all global destinations, or accept all payment options. And, while most sell individual doses, with discounts for purchasing multiple doses at one time, a few offer long-term contracts. Therefore, details from all of the following three pages will need to be considered in conjunction in order to make the best decisions about which organism(s) will meet each user’s unique needs and circumstances, and where to purchase them.
Some would-be hookworm hosts may consider traveling to an area where these worms are endemic, in the hope of acquiring their larvae at zero cost in the same way that the locals do - by walking barefoot in open-air latrines. For a number of reasons, this is a not a good idea, as is explained here by the only Westerner who has ever done this.
Working with a doctor
At the present time, helminthic therapy is not approved as a medical treatment anywhere in the world, so doctors face the possibility of losing their medical licence if they become involved In its use. Fortunately, helminthic therapy does not need to be doctor-led because, in practice, it is little different from taking a probiotic, which most people do without involving a doctor.
One of the purposes of this wiki is to provide everything that the helminth self-treater needs in order to use this therapy safely, but it is essential that would-be users familiarise themselves fully with all the site’s contents before commencing their treatment.
While a doctor's involvement is not essential, it can be helpful to have medical support available during the early stages of helminthic therapy. For example, a doctor will be able to prescribe an immunosuppressant drug to ease helminth side effects if these were to become troublesome, or prescribe an anthelminthic drug if termination of a worm colony became necessary. But exactly how much to involve a physician is a matter for each self-treater to decide for themselves, based on their knowledge of their own practitioner.
Some doctors, especially naturopathic ones, may be willing to recommend helminthic therapy and become involved in its use, and a few may act as an intermediary in the supply of helminths to their patients. However, most doctors are poorly informed about helminthic therapy, and even those who do have some understanding of it can sometimes give their patients incorrect advice. For example, one patient was told by a doctor that worms won’t work in someone who has SIBO, which is not the case. See Helminthic therapy and small intestinal bacterial overgrowth (SIBO).
If a doctor offers to supply helminths, their prices should be checked against those of the online helminth providers, who will likely be considerably cheaper. Some doctors have claimed that the worms they supply are “stronger”, more effective, or even safer, than those available online, but the only possible difference is between fresh HDC and commercially prepared HDC, and correct dosing with commercially prepared HDC fully compensates for their slightly reduced effect in comparison with fresh HDC. See Dosing with HDC.
Most doctors are dismissive of helminthic therapy, some are even hostile to its use, and many intensely dislike patients taking matters into their own hands to try any experimental treatment. Fortunately, all that is required from a doctor is that, while the patient is using helminthic therapy, they continue to provide the routine medical care that they would normally provide.
If a helminthic therapy self-treater decides to tell their doctor what they are doing, the language used can be important because, if a doctor thinks that their permission, approval or cooperation is being sought, they may feel they have no choice but to refuse to become involved in any way. To avoid placing a doctor in a difficult position, they can simply be informed by the patient of their intention to pursue the therapy. This lets the doctor off the hook and gives them the option of ending the relationship if they feel uncomfortable about it.
Doctors should certainly not disparage this therapy nor try to dissuade their patients from using it, especially if they are not fully conversant with the therapy. Any physician who does arbitrarily discourage self-treatment with helminths, in disregard of all the available research and anecdotal evidence would clearly be violating the Hippocratic principle of primum non nocere (first, do no harm) and, in acting in this way, would arguably be committing medical abuse.
One patient who took copies of a few selected scientific papers to show her doctor, and explained what she’d learned about the therapy, reported that, after glancing through the literature, the doctor responded as follows.
Here are comments by other patients who have found their doctors to be supportive of their decision to try helminthic therapy.
But some doctors are completely closed to even learning about this therapy. When an extensively published and award-winning toxicologist presented the head of adult allergy and asthma at his local university with papers about helminthic therapy, she refused to consider them and promptly fired him as a patient. 
Another self-treater whose doctor was not supportive found it necessary to locate a new one when he needed a prescription for prednisone to help ease the initial side effects after inoculating with too many hookworms. He did this by identifying all the most alternative and “hippie-looking” doctors in his area and emailing them. While most of them declined to help him, two agreed, and the one he selected carried out before-and-after blood tests and was willing to prescribe whatever he needed.
One self-treater takes a very proactive approach when introducing the subject with a doctor.
For further help with talking to a doctor about helminthic therapy, see the following resources.
- Helminthic Therapy Reading packet. (A list of scientific papers that are suitable to be given to a doctor.)
For a list of doctors who are experienced in the use of helminthic therapy and offer remote consultations via telephone and Skype, see the following page.
Combining helminthic therapy with drug treatments
No problems have been reported by anyone starting helminthic therapy using NA, TTO or TSO while already taking one of the following immunosuppressive medications.
Cyclosporin; synthetic corticosteroids including prednisone and its active metabolite, prednisolone; the thiopurines, azathioprine and mercaptopurine/6-MP (purinethol); the TNF inhibitors, infliximab (Remicade), adalimumab (Humira), certolizumab pegol (Cimzia) and golimumab (Simponi); humanized antibody drugs, e.g., omalizumab (Xolair); humanized monoclonal antibody drugs such as natalizumab (Tysabri); and recombinant fusion protein drugs such as etanercept (Enbrel).
The detail sheet for some immunosuppressant drugs - for example dupilumab (Dupixent) - may advise that helminth infections should be treated before commencing use of the drug. This advice is to prevent immunosuppression by the drug from supporting the proliferation of pathogenic helminths, but this is not an issue for users of NA, TTO or TSO because these species cannot proliferate within a host. However, it may not be advisable for anyone to take HDCs who is immunocompromised as a result of treatment with major immune-suppressive drugs, or due to HIV/AIDS or a genetic condition. 
It can actually be an advantage to be taking one of the above drugs in the early stages of helminthic therapy using NA, TTO or TSO because the drugs reduce, and often completely prevent, the transient side effects sometimes caused by the introduction of helminths, especially NA.
People who are already taking a daily dose of prednisone when they begin helminthic therapy - often 15 or 20 mg per day - experience little or no side effects after inoculation, and those who have used this drug on a short-term basis specifically to reduce side effects have found that 5 or 10 mg per day is usually sufficient for this purpose.
If prednisone is used specifically to relieve side effects, the prescribing doctor will determine a taper to wean their patient off the drug and, if the symptoms return, they may be willing to defer the taper.
Immunosuppressive drugs can help human helminths to become established by reducing intestinal inflammation, so anyone who is already on one of these drugs should resist the temptation to stop taking them too soon after introducing NA or TTO. As the majority of those who respond to this therapy don’t see significant or consistent benefits until at least 3 months after their first inoculation, it would arguably be unwise to stop taking an immunosuppressant drug before this, whichever worm species is being used. In fact, many users have found it best to continue with the drug treatment beyond this point because some people only start to improve between 6 and 9 months, some only after 9 months, and a few not until between 18 and 24 months. Even helminth hosts who see early benefits can continue to experience periodic exacerbations or flares of their disease for up to 18 months, and a few may need to continue to take medication alongside helminthic therapy in the longterm.
In view of this wide variation in experience, each individual must decide, in consultation with their physician, how long into their therapy to continue with an immunosuppressive drug before beginning, very slowly, to taper the dose. However, one supplier of human helminths (NA and TT) has been very specific about this and advised waiting until at least five months have elapsed after achieving a substantial improvement in symptoms. 
This is particularly important for subjects with Crohn’s disease, or one of the other intestinal diseases, because they tend to have a vigorous immune response to helminths, so suddenly stopping a drug that has been keeping this response in check may cause a rebound effect that could result in a flare and, potentially, a loss of worms in the case of NA or TTO.
One individual with IBD-related arthritis found that reducing prednisone too soon caused her joints to ache and stiffen, so she continued to take azathioprine (Imuran) on its own after stopping prednisone, and this provided an intermediate step which allowed her to wean herself off drugs altogether, a process that took between 8 months and a year. 
A few drugs are harmful to helminths, and those that can adversely affect NA and TT are listed in the Human Helminth Care Manual. These drugs include oral and injected antibiotics, the effects of which can be such that there may be little point in using NA, or possibly TT, if there is a need to take antibiotics regularly, or on a longterm basis. Those drugs that are incompatible with TSO are listed here, and those that are best avoided by users of HDC are listed briefly here.
Considering the cost of helminthic therapy
At first sight, helminthic therapy may appear to be expensive, especially to those who live in countries with free health care, but a number of factors need to be taken into consideration, including the following.
1. Compared with other treatments used for the conditions that helminthic therapy treats, it is extremely cost-effective. For example, TSO is only 1/5th of the cost of Remicade, and the other helminths are even cheaper than this.
2. There is a good chance that helminthic therapy users will be able to earn more after treatment than they could before.
3. People who smoke, and many others with a variety of interests and hobbies, often pay out far more than the cost of helminths just to provide themselves with pleasure and entertainment.
4. Please look carefully at the details for each of the companies on the Helminth providers page. There is considerable variation in what is on offer, and discounts and payment plans may be available to those who ask. You may be able to work out something more manageable if you talk to each of the providers who are offering the species of helminth that you want and are willing to ship to your location.
If you are still unhappy with the cost of helminths, you can grow your own NA, HDC or TTO. Incubating the first two of these species is well within the ability of most people if they follow the detailed instructions on the Helminth incubation page, but a single first dose will need to be purchased from a provider to start the process.
DIY helminth incubation
Three of the four species of helminth that are used in therapy are suitable for DIY incubation at home. See Helminth incubation. However, if you intend to incubate hookworms, it is recommended that you obtain your starter dose from an established provider because this will obviate the risk of acquiring a different and possibly harmful species of worm, or some other unwanted infection, from another self-treater. See Hookworm incubation issues for more about these risks.
See the separate page:
Enquirers who use a search engine to locate information about helminthic therapy will find some good sources, such as research papers and the main sites of the Helminth providers. Unfortunately, mixed in amongst these sources are many less reliable ones, including a veritable graveyard of neglected websites and blogs, many of which were created in the early days of this therapy. Some of the information on these sites is now out of date and perpetuating misconceptions from a time when much about the therapy was still a matter of conjecture.
Some of the larger health information websites carry pages about helminthic therapy but many of these contain factual errors, some of which can create serious misconceptions.
For example, an article on the Healthline website entitled, Helminthic Treatment for Crohn's Disease speaks of worm eggs being “injected” into patients, and helminths causing dangerous side effects over time, including anaemia, protein deficiency and stunted growth. However, none of these claims are true in the case of the four species of mutualistic helminth being used in small numbers in helminthic therapy, as can be seen from the following wiki pages.
Editors of this wiki have made several attempts to have the errors in the Healthline article corrected, but no one has ever responded to any communication about the article, a situation that is typical for most of the large health information websites, many of which have been acquired by pharmaceutical companies and are controlled by their representatives.
In view of these issues with online health sites, anyone who is seeking information about helminthic therapy is urged to use this wiki as their primary source. It is the definitive database of information about all aspects of the therapy and is updated daily by volunteer citizen scientists who are directly involved in pioneering its use.
- A helminthic therapy and microbiome immune support resource centre that’s friendly to those who are brain fogged, exhausted or in pain.
- An article for those who are interested in helminthic therapy but are reluctant to try it because of an aversion to worms.