Application area · Autism and ADHD

Autism and digestive symptoms: what restoring the gut flora can realistically do

A large proportion of children living with autism spectrum disorder also have recurrent constipation, diarrhoea, bloating and abdominal pain, and the behavioural difficulties that follow from them. Microbiota transfer therapy is aimed primarily at these digestive symptoms — under the direction of a treating physician, from a measurable baseline, with realistic expectations.

Before we begin

We know this is not your first attempt

So we start not with a promise, but with numbers, limits and prices.

If you have found your way to us, this is probably not the first thing you have tried with your child. Many parents have already changed the diet, used food supplements and been given promises that did not work out. Meanwhile the same symptom patterns reappear every morning.

We do not make promises. We ask you to read what the numbers show, where the limits of the therapy lie, and what the first step costs. You then make the decision, together with your treating physician.

Six questions

Is this for my child?

This is not a diagnosis and does not replace a medical examination — but in one minute it shows whether it is worth getting in touch with us.

Who we cannot take on

If the child is immunosuppressed, is undergoing active oncological treatment or has a serious underlying illness; if there is an acute infection, fever or an unclarified abdominal condition — in these cases we currently cannot undertake to provide the capsules. If you are unsure which category you and your child fall into, ask for a telephone consultation and in 15 minutes we will talk the options through. If we see that we cannot help, we will say so honestly.

Timing expectations

When to expect what

So that you know when things happen and where the decision points are.

Week 0

Registration and the start of therapy

Recording the patient's details, filling in the “Goals and expectations” questionnaire and, if you wish, a telephone consultation. Once the parent has made the decision, the compatibility test begins — and with it the microbiota transfer, since the test is itself a low-dose MTT. The therapy therefore does not start in week 10, but here.

Week 5

Evaluating the test

We evaluate the test, select the appropriate LOT, fill in the exposome questionnaire together, and dose determination begins: with a biological trial we establish what quantity of the selected donation gives the most effective response. By now it becomes clear whether there is a capsule with which the body works properly, and it also shows what lifestyle changes will be needed. Decision: whether we move on to finding the dose density, so that MTT can start.

Week 10

The therapeutic dose

We determine the dose to be used. MTT has been running at a low dose since week 1; from here it continues at the therapeutic dose, and it is from this that real, continuous change in condition can be expected. By this point all the data are available. Decision: whether we move on to the minimum 60-day, full-dose phase with the capsule of the selected dose and LOT number.

Week 18

Stability, then tapering off

Stability should be reached by now, and capsule use becomes an everyday routine. Decision: is further improvement expected from taking the capsules or from a change of LOT? If not, we begin tapering off: every 7–10 days we reduce the total number of capsules taken over two days by one.

This is how the process works

Your path, step by step

The same sequence as on the timeline above. At every stage you will know what the next step is.

Contact and pre-screening

Fill in the form or ask for a call back. In a free, 15-minute conversation we clarify whether it makes sense to start in your child's case. If we see that it does not, we will say so.

Registration and goal-setting

We will send you a link by e-mail with which you can register as a patient. At that point you will receive a unique identifier from us in P0000000 format. We record the patient's details, and you fill in the “Goals and expectations” questionnaire.

FindBiome: this is where therapy starts

FindBiome is the compatibility test itself: it shows which donor your child's microbiome matches best. Since the capsule is a low-dose microbiota transfer, the therapy begins with this step. We assemble the capsules within 72 hours and they are ready for shipping. This is a paid step, but it does not commit you to continuing.

Evaluation, LOT selection, exposome

The week 5 we evaluate the test and select the appropriate LOT. Together we fill in the exposome questionnaire: we review lifestyle, nutrition and possible environmental exposures. Dose determination begins with a biological trial.

Therapeutic dose and TransferBiome

In week 10 we determine the dose to be used, and treatment continues at the full, therapeutic dose: a minimum 60-day phase with the capsule of the selected dose and LOT number.

Stability, follow-up, tapering off

The symptom diary and regular consultation accompany the whole process. By week 18 stability must be reached. If no further improvement is expected, we gradually taper the capsule off, reducing by one every 7–10 days.

Transparent pricing

What the procedure costs, and when you have to decide

You do not have to decide about the whole process at once. After every step you have the opportunity to assess the results achieved and to weigh up the potential change in condition.

StepWhat we providePriceMust you continue?
1. Call back and pre-screeningA 15-minute conversation, clarifying suitabilityfree of chargenot
2. FindBiome compatibility test
4×15 capsules
Testing donor–recipient matching, at the same time a low-dose MTT, the first phase of the therapy1.140 €
+ shipping cost
not
3. Exposome consultationAssessment of environmental and lifestyle exposures, shared goal-setting (with a DynaMAP baseline if required)185 €
the DynaMAP can be ordered separately: €325 (professional) or €575 (comprehensive)
not
4. TransferBiome course
60 / 3×60 capsules
Personalised composition, full protocol + follow-up (the quantity prescribed is decided during the biological trial)€1,350 / 60 capsules

What the price includes, and what it does not

ItemIncluded?
Call back and pre-screening (15-minute conversation)yes — free of charge
FindBiome compatibility testseparate item: 1,140 €
Exposome consultationseparate item: €185
DynaMAP microbiome profilecan be ordered separately: €325 (professional) or €575 (comprehensive)
Appearing in personis not necessary — the process is remote throughout
The capsules in the packaging unit orderedyes — at the price in the table above
Shipping costnot — the delivery charge is separate
Follow-up during the courseyes
Joint closing assessment and tapering-off planyes
Examination by the treating physician, laboratory testsnot — these take place at your own healthcare provider
The compatibility test is a step that makes sense on its own. It shows which of the available donors' microbiota best matches your child's bacterial matrix. If we do not find a suitable one, we will tell you after the test and we will not recommend continuing. We assemble the capsules within 72 hours of the order, and they are ready for shipping.
The right treatment

Which capsule is for what?

The same high-quality donor microbiota, processed in a certified laboratory — in two steps, tailored to your situation.

Compatibility test

FindBiome

4×15 capsules
  • Testing donor–recipient compatibility to select the best-matching donor — at the same time a low-dose microbiota transfer, that is, the first phase of the therapy
  • A tool for the preliminary assessment that underpins the questions of the exposome consultation
  • from €1,140 — a low-risk first step that does not commit you to continuing
  • Minimum order: 1 packaging unit (4×15 capsules)
FindBiome details
MTT therapy

TransferBiome

60/3×60 capsules
  • After the compatibility test, the course continued with a personalised composition
  • Exclusively under the direction of the treating physician, with continuous follow-up
  • €1,350 / 60 capsules, or €3,500 / 180 capsules. The capsules are ready for shipping within 72 hours of the order.
  • Following a protocol refined on the basis of the exposome consultation
TransferBiome details
Evidence

What we know today — in brief

The data are strongest for the digestive symptoms. The 2025 systematic review found symptom reductions of 35–82% in the uncontrolled studies, and the longest follow-up measured a symptom score 58% lower even two years after treatment.126, 123

For the behavioural symptoms the data are contradictory. In the two controlled studies to date, no significant difference was demonstrated on the primary endpoint in either case; improvement appears more consistently on the parent- and clinician-rated scales. The uncontrolled studies show a more favourable picture, but they carry a high risk of bias.124, 125

The safety data are reassuring, but not flawless. No serious adverse event has so far been reported in children; in the double-blind trial, however, somewhat more adverse events occurred in the treated arm (23% vs. 14%).126, 124 The treatment does not cure autism.

Scientific background →

Why the gut

The gut–brain axis and autism/ADHD

Among people living with autism spectrum disorder and ADHD, gut dysbiosis[G] — an upset in the balance of the gut flora, also known as the gut microbiota — and the digestive symptoms that accompany it are often seen: bloating, constipation or diarrhoea. These complaints reduce quality of life in themselves, but at the same time, through the gut–brain axis the gut microbiota is also closely linked to the central nervous system.

BRAIN GUT Neural pathway The vagus nerve maintains a direct, two-way connection. Immune and inflammatory pathway The state of the gut wall influences the body's inflammatory responses. Metabolic pathway Microbial metabolites also act as signalling molecules.
  • Neural pathwayThe vagus nerve maintains a direct, two-way connection.
  • Immune and inflammatory pathwayThe state of the gut wall influences the body's inflammatory responses.
  • Metabolic pathwayMicrobial metabolites also act as signalling molecules.

A schematic diagram of the main pathways described so far; on the metabolic pathway, for example, short-chain fatty acids act as signalling molecules. The existence of the connection is well documented; how far changing the microbiota modifies the behavioural symptoms is still an open question.

Microbiota transfer therapy (MTT) — commonly known as faecal transplantation — works by introducing gut microbiota from a thoroughly screened, healthy donor in capsule form, in order to restore the disturbed balance. As far as we know today it does not cure autism or ADHD, and it cannot be used in the same way in everyone affected. For more detail, the Microbiota Guide and the Microbiota Handbook are worth reading.

And what about ADHD? An important distinction: the studies cited above were, without exception, carried out in children living with autism spectrum disorder. Clinical data on ADHD are essentially unavailable. If a persistent digestive complaint accompanies ADHD, we can consider the request on an individual basis — but here we can say even less about the behavioural symptoms.

What parents ask most often

Safety you can rely on

Donor screening

Every donor goes through our DSQ donor screening framework.

Batch identification

Every capsule we ship carries a LOT number (a manufacturing batch identifier), so it can be traced back to the donor at any time.

Compatibility in advance

The compatibility test performed with FindBiome shows even before the therapeutic dose is used whether there is a matching donation.

Medical supervision throughout

We do not start a protocol without a treating physician. The capsule is in every case prescribed by the treating physician.

Follow-up

The symptom diary is used throughout the full 6–8 month protocol, with follow-up consultations: this is how it becomes clear how your child responds to the transfer.

Known side effects

No serious adverse event occurred in the clinical trials; mild, transient complaints did (diarrhoea, abdominal discomfort, slightly raised temperature).

Environment and lifestyle

The role of the exposome

The exposome is the totality of environmental exposures acting across a whole lifetime: nutrition, toxin burden, antibiotic use, stress, sleep quality and general lifestyle all continuously shape the gut microbiota and the signalling it mediates through the gut–brain axis. We are convinced that the state of the microbiota cannot be interpreted separately from the genetic background and environmental factors.

That is why an integral part of the process is a targeted exposome consultation: we map lifestyle, eating habits and possible toxin burden, then, if required, supplement this with DynaMAP profiling; this gives the measurable baseline against which later results can be compared. To help you rethink nutrition, our Foods database is also a help.

Deliberately putting the exposome in order: the foundation of the therapy. Rethinking nutrition, reducing toxin exposure, regular good-quality sleep and effective stress management all contribute to making microbiota-based support as effective as possible.
Common questions

What parents usually ask us

Can my child swallow the capsule?
The capsules can, if necessary, be opened, and their contents mixed into cold food or drink (for example apple purée, a favourite fruit juice or yoghurt). With small children and selective eaters we discuss this separately during the preliminary telephone consultation, and if intake cannot be managed, we say so in advance: we do not start a course that the family cannot see through.
How soon will we see anything?
With digestive symptoms, the studies typically measured a meaningful difference around week 8. With us the microbiota transfer already starts with the compatibility test, in week 1, at a low dose; the therapeutic-dose phase begins around week 10 and lasts at least 60 days. The full protocol, including tapering off, is 6–8 months, with a symptom diary throughout — this is when it becomes clear whether your child responds. The two-year follow-up suggests that the improvement achieved in the digestive symptoms may be lasting — but that was a study without a control group, in which 12 of the 18 participants also changed their medication, their food supplements or their diet over the two years.123
What happens if nothing improves?
It happens that a child does not respond to the treatment, but this already becomes clear during the compatibility test. There are three decision points in the process (in weeks 5, 10 and 18), and you can stop at any of them. If the symptom diary shows no meaningful change, we do not recommend going further; and at week 18 we decide whether further improvement can still be expected, or whether we begin tapering off. We do not build in automatic repetition.
Will it cure autism?
No. Microbiota transfer therapy targets the digestive symptoms and the behavioural anomalies. The data on the behavioural symptoms are contradictory: the uncontrolled studies show improvement, but on the primary endpoint of the two controlled studies no difference was demonstrated. Anyone who promises you a cure is claiming something that today's data do not support.
Is this safe for a child?
In the 2025 systematic review pooling data from 394 children and adolescents, no adverse event was classified as serious in any of the six studies that examined safety; the complaints reported were mild and transient. Three studies did not address the question of safety.126 In the double-blind trial, adverse events were somewhat more frequent in the treated group than in the placebo group (23% vs. 14%); the most common event was fever, which occurred at a similar rate in both groups, and the difference was mainly due to the neurological and psychiatric events recorded (8 vs. 2). No serious event occurred in either group.124 This is a relatively small number of patients overall, which is why we insist on supervision by a treating physician.
Where does the donor material come from and how is it screened?
Every donor goes through our DSQ donor screening framework covering bacteriological, virological, parasitological and serological testing, stool testing and detailed medical-history screening. Every capsule shipped can be traced by its LOT number. The details are set out in the Clinical Protocol Guide, which is available to download.
Is a treating physician needed? I cannot persuade our paediatrician.
Yes, one is needed. If your treating physician is uncertain, send them the MTT Clinical Protocol Guide v7.1 PDF — we wrote it for colleagues, with references. On request our specialist will speak with them directly. If you would like us to, we will refer you to a suitable specialist (languages spoken: English, Hungarian).
And what about ADHD?
Considerably less data are available for ADHD than for autism — the studies cited were, without exception, carried out in children living with autism spectrum disorder. If a persistent digestive complaint accompanies ADHD, we can consider the request on an individual basis, but here we can say even less about the behavioural symptoms.
Should we stop the current treatments or the diet?
No. Do not change anything without consulting your treating physician. The protocol fits alongside existing care, not instead of it.
What is the smallest quantity that can be ordered?
For the FindBiome compatibility test we use 1 packaging unit (4×15 capsules). For the TransferBiome course, 60 capsules.
How long does the whole process take from applying?
The call back happens within 1–2 working days. We assemble the capsules ordered within 72 hours and hand them over to the courier service ready for shipping.
What is the legal and regulatory background?
Microbiota transfer therapy is not a licensed indication in autism. We provide the service within the framework of individual care directed by a treating physician. This service is not a substitute for professional medical advice, diagnosis or treatment — the decision to use it rests in every case with the treating physician.

More questions

Downloadable materials

Parent guide and digestive symptom diary

We have summarised what is worth knowing before the decision — the numbers, their limits, the eligibility criteria and the decision points of the process — and attached a symptom diary covering two weeks. Filling in the diary is useful in itself: it gives a more accurate picture of your child's complaints, and if you start later, it becomes the baseline. You can also take it with you to your treating physician.

Parent guide + symptom diary (PDF) →

For treating physicians

If you are a treating physician, or the parent asks you for an opinion: treatment follows the MTT Clinical Protocol Guide v7.1 which sets out patient selection, dose determination, the rules of escalation and gradual tapering, donor screening requirements and the follow-up steps — everything you need for the decision at the bedside. Referring a patient requires no separate agreement: a single message is enough and we will initiate the professional consultation.

Clinical Protocol Guide v7.1 (PDF)Professional consultation →

Get in touch

Let's talk about your child's digestive symptoms

Write and tell us what you are struggling with. We will look at whether it makes sense to start in your child's case — and if we see that it does not, we will say so.

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MicroBiome Bank does not sell products; it connects donors and recipients by providing professional medical services: it organises the recruitment of donors and their screening in a certified laboratory, the stool tests, and the processing of the screened donation into capsule form. The contents of the capsules remain the property of the donor until the recipient has paid in full. The brand names of the services serve to make them easier to remember. It is important to emphasise that in autism and ADHD, microbiota transfer therapy can offer support only in certain forms and with individual responses — it is not a cure. We deliver the capsules “to the doctor's hand”, and they are to be used under the guidance of a treating physician. For detailed information, please contact us.

The MicroBiome Bank service is not a substitute for professional medical advice, diagnosis or treatment. The decision to use it rests in every case with the treating physician.