You have been told your labs are normal and your colonoscopy was clean, and you still cannot eat a normal meal. Here is who actually handles what — and which symptoms mean you should see a gastroenterologist first, not us.
The short answer
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Three kinds of clinician, different jobs — Primary care screens and rules out. A gastroenterologist diagnoses and excludes structural disease. Functional medicine works on why a functionally normal gut still is not working.
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Red flags go to gastroenterology first — Blood in the stool, unintentional weight loss, iron-deficiency anaemia, diarrhoea that wakes you at night, or new symptoms over 50 need a GI evaluation before anything else.
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A clean colonoscopy is not a dead end — It rules out serious disease, which is its job. It does not explain bloating, urgency or food reactions — and it was never designed to.
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Often you want both — The most reliable path for stubborn gut symptoms is a gastroenterologist who has excluded disease and a functional workup that looks at what is driving the dysfunction.
What Kind of Doctor Treats Gut Problems?
Three types of clinician treat digestive problems. A primary care physician handles first-line evaluation, basic labs and referral. A gastroenterologist is the specialist in the structure and disease of the digestive tract — endoscopy, colonoscopy, imaging, and the diagnosis of conditions like coeliac disease, inflammatory bowel disease and cancer. A functional medicine clinician investigates why a digestive system with no structural disease is still not functioning, using detailed history, targeted testing and nutrition-based protocols.
Most people with chronic bloating, irregular bowels or food reactions end up seeing at least two of the three, usually in that order, and often feeling that each one handed them off. That experience is common enough to be worth naming: the tests were appropriate, the results were genuinely reassuring, and the symptoms did not change. Being told nothing is wrong when you do not feel well is not a diagnosis, and it is not a reason to stop looking. Food changes are usually part of the plan, and our leaky gut diet page lists what patients commonly add and remove.
- Primary care physician
- First evaluation, baseline blood work, coeliac screening, stool studies, and referral onward. The right first call for most new digestive symptoms.
- Gastroenterologist
- Endoscopy and colonoscopy, imaging, biopsy, and the diagnosis or exclusion of structural and inflammatory disease. Essential when alarm features are present.
- Functional medicine clinician
- Extended history, breath and stool testing, nutrition and microbiome-directed protocols for symptoms that persist after disease has been excluded.
- Registered dietitian
- Structured dietary work — low-FODMAP trials, elimination and reintroduction — done properly and safely, ideally alongside medical care.
Gastroenterologist or Functional Medicine — and When You Need Both
These are not competing options and it is unhelpful to present them as rivals. They ask different questions.
Gastroenterology asks: is there disease here? That question has to be answered, and the tools to answer it — scopes, biopsies, imaging — belong to gastroenterology alone. Nothing in functional medicine substitutes for a colonoscopy, and any practitioner who implies otherwise is doing you harm.
Functional medicine asks: given that there is no disease, why is this system behaving badly? That is a question about motility, bacterial populations, digestive capacity, food triggers, stress physiology and what happened before the symptoms started — a course of antibiotics, a bout of food poisoning, a stressful year. It is a slower, more granular investigation, and it is where a lot of chronic gut complaints are actually resolved.
The same patient, two different workups
Gastroenterology focus
- Exclude cancer, IBD, coeliac disease and structural causes
- Colonoscopy, upper endoscopy, biopsy, imaging
- Diagnosis by exclusion once alarm features are absent
- Management often symptom-directed — antispasmodics, laxatives, neuromodulators
- Endpoint: a confident diagnosis and no dangerous disease
Functional medicine focus
- Explain persistent dysfunction after disease is excluded
- Breath testing, comprehensive stool analysis, targeted nutrient and inflammatory markers
- Diagnosis by pattern — what changed, when, and what maintains it
- Management protocol-directed — diet, antimicrobial or botanical courses, motility support, repletion
- Endpoint: symptoms that actually change
The practical sequence we recommend to most people: see primary care, get the basic screening including coeliac serology, and get a gastroenterology referral if there is any alarm feature or if you are due for colorectal screening. Then, if the scopes are clean and you are still unwell, bring that work to a functional evaluation rather than starting over. We would far rather read your existing gastroenterology results than repeat them. The full range of what we work on is set out in the digestive health conditions we treat, and we are explicit about which of them need a specialist alongside us.
Red Flags That Mean See a Gastroenterologist First
This section matters more than the rest of the page, so it comes before the interesting testing discussion rather than after it.
The ACG clinical guideline on irritable bowel syndrome defines a set of alarm features that change the plan. If you have any of them, the correct next step is a gastroenterologist, and a functional workup should wait. Not because functional medicine cannot help you eventually, but because these symptoms can indicate disease that needs excluding now.
Alarm features
See a gastroenterologist before anything else if you have
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Blood in the stool, or black tarry stools, not clearly explained by haemorrhoids.
This needs prompt gastroenterology evaluation. Do not wait to see whether a diet change helps.
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Unintentional, unexplained weight loss.
Bring this to your physician now — it is one of the strongest reasons to investigate structurally.
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Iron-deficiency anaemia with no obvious cause.
Requires evaluation for a source of blood loss in the digestive tract.
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Diarrhoea that wakes you from sleep, or symptoms that consistently wake you at night.
Nocturnal symptoms point away from functional causes and need specialist assessment.
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A mass felt on abdominal or rectal examination, difficulty swallowing, or persistent vomiting.
Urgent gastroenterology referral.
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New or changed bowel symptoms starting after age 50, or a family history of colorectal cancer or inflammatory bowel disease.
Get screening and a specialist opinion first; the threshold for investigating should be low.
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Fever, night sweats, or markedly raised inflammatory markers alongside digestive symptoms.
Suggests an inflammatory or infectious process rather than a functional one.
We turn people away for this reason, and we would rather say so publicly. If you call us with rectal bleeding and weight loss, we will tell you to see a gastroenterologist and we will be glad to look at what they find afterwards. A practice that takes that case straight into a six-month gut protocol is not being holistic; it is being negligent.
Equally worth knowing: the ACG guideline notes that in patients with IBS and no alarm features, the diagnostic yield of colonoscopy is low and comparable with people who do not have IBS. That cuts both ways. It means a clean scope in the absence of red flags was the expected result rather than a failure — and it means repeating it in the hope of an answer is unlikely to give you one.
The Testing a Root-Cause Gut Workup Uses
Once disease is off the table, the question becomes mechanical and microbial. These are the tests that tend to earn their place, with honest notes on what each can and cannot tell you.
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Hydrogen and methane breath testing for SIBO
You drink a measured sugar solution — usually lactulose or glucose — and breath samples are collected at intervals to measure hydrogen and methane produced by bacteria fermenting it in the small intestine. A rise within the first 90 minutes suggests small intestinal bacterial overgrowth; a high methane picture suggests a methane-predominant pattern more often associated with constipation. Breath testing is the practical, non-invasive option and it is what most SIBO diagnoses rest on. It is also imperfect: preparation errors, transit speed and test substrate all affect the result, so it is interpreted alongside your history rather than as a verdict on its own.
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Comprehensive stool analysis
More informative than a standard stool culture. Useful markers include pancreatic elastase for digestive enzyme output, calprotectin as an inflammation screen, secretory IgA, and the balance of bacterial populations. Worth doing when symptoms suggest maldigestion, dysbiosis after antibiotics, or when inflammation needs quantifying without another scope. Interpret the microbiome portion with humility — it describes a population, not a diagnosis.
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Coeliac serology, if it has not been done
Non-negotiable and frequently skipped. It must be done while you are still eating gluten, which is why we ask before anyone starts an elimination diet. Removing gluten first invalidates the test and can delay a real diagnosis by years.
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Food sensitivity panels, used carefully
IgG food panels are popular and widely over-interpreted: they indicate exposure rather than clinical reaction, and they routinely flag foods you tolerate perfectly well. We use them as a hypothesis generator at most. A supervised elimination and structured reintroduction remains the more reliable way to identify a genuine trigger, and we set out the distinction plainly in what food sensitivity testing measures.
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Basic markers most people already have
Full blood count, ferritin and iron studies, B12 and folate, vitamin D, thyroid function, and inflammatory markers. Cheap, widely available, and frequently the place an overlooked explanation is sitting — particularly thyroid disease, which alters transit in both directions.
Why IBS Often Does Not Improve on Medication Alone
IBS medication is aimed at symptoms: slow the bowel down, speed it up, relax a spasm, dampen the pain signalling. For a proportion of people that is enough and there is nothing wrong with taking it. For many others the symptoms return the moment the medication stops, because nothing that was driving them changed.
The drivers we see most often are a bacterial overgrowth that was never tested for, a motility problem left behind by a gastrointestinal infection, low digestive enzyme or acid output producing fermentation further down, a genuine food trigger that has never been isolated properly, and the physiological effects of sustained stress on gut motility and sensitivity. Several of these are treatable, and several of them recur if the underlying pattern is not addressed — which is why our notes on the reasons SIBO is not improving keep coming back to relapse rather than to the initial treatment.
It is also why we spend the first appointment on history rather than on tests. When the symptoms started, what happened in the weeks before, what makes them better, what the bowel pattern actually looks like across a week, what has already been tried and what happened — that narrative decides which tests are worth running. Our broader work on IBS and gut dysbiosis goes further into what that investigation tends to surface.
One honest caveat: this approach takes longer and involves more of your own effort than a prescription. Dietary trials take weeks. Protocols run in phases. Some people improve substantially, some partially, and a few not at all. We would rather set that expectation at the start than sell certainty we cannot deliver.
Gut Care in Florida
The Florida Center For Functional Medicine works with patients across the state — in and around Jacksonville and St. Augustine, Orlando, Naples, Boca Raton, West Palm Beach, Weston and Aventura and the wider South Florida corridor — and by telehealth for patients anywhere in Florida. Digestive complaints are among the most common reasons people come to us, usually after a normal workup somewhere else.
Practically, that means you do not need to live near one of our offices to be seen. Gut work is well suited to virtual care: the history is long, the testing kits ship to your home, and the follow-ups are conversations about how you are responding. What it still requires is that anything structural has been excluded locally, which is why we ask for your existing records before the first visit rather than after it.
Cost is a fair question to ask early, and we publish it rather than making you call for it — our breakdown of functional medicine cost in Florida covers what visits and testing typically run and what insurance usually will and will not cover. If you want to talk it through before committing, a free digestive health consultation is the place to start: a short conversation about whether your case is one we can genuinely help with, or one that belongs with a gastroenterologist first.
Common Questions
QGastroenterologist or functional medicine — which should I see first?
For new digestive symptoms, start with primary care and go to a gastroenterologist if there is any alarm feature — bleeding, unexplained weight loss, iron-deficiency anaemia, night-time diarrhoea, difficulty swallowing, a palpable mass — or if you are due for colorectal screening. If the workup is clean and you are still symptomatic, that is the point at which a functional evaluation adds something. The two are complementary, and for stubborn cases you often want both.
QWhat tests actually diagnose SIBO?
In practice, hydrogen and methane breath testing after a measured dose of lactulose or glucose. A rise in hydrogen within roughly the first 90 minutes suggests bacterial overgrowth in the small intestine, and a raised methane pattern is associated more with constipation-predominant symptoms. Small bowel aspirate and culture is the technical reference standard but is invasive and rarely done. Breath testing is imperfect — preparation and transit time both affect it — so results are read together with your history rather than alone.
QWhy has my IBS not improved on medication?
Because most IBS medication targets the symptom rather than the driver. If a bacterial overgrowth, a post-infectious motility problem, low digestive enzyme output or an unidentified food trigger is maintaining the picture, symptoms return when the medication stops. That is not a failure of the medication; it means the next question has not been asked yet.
QIs a stool test worth doing?
Often yes, if you choose what you are looking for. Pancreatic elastase for enzyme output, calprotectin as an inflammation screen and a read on bacterial balance after antibiotics are all genuinely useful. Be more sceptical about the microbiome interpretation sections and the supplement recommendations that some panels generate automatically — those are marketing layered onto data, and we read the markers rather than the summary.
QWhen is a colonoscopy the right next step?
Whenever an alarm feature is present, when you are due for colorectal cancer screening, if you have a family history of colorectal cancer or inflammatory bowel disease, or if your symptoms have changed in character. Guidelines also support considering it where microscopic colitis is a realistic possibility — older age, female, and more intense diarrhoea. In IBS without alarm features, the yield is low, which is a reason for reassurance rather than for repeat scoping.
QDo you see gut patients by telehealth in Florida?
Yes. We see patients throughout Florida by telehealth, including Jacksonville, St. Augustine, Orlando, Naples, Boca Raton, West Palm Beach and the South Florida corridor. Testing kits are shipped to you and follow-ups are virtual. We do ask that structural disease has been excluded locally first, and we will review your existing gastroenterology records as part of the intake.
Start with a conversation, not a protocol
If your scopes were clean and your symptoms are not, a short consultation will tell you whether a root-cause workup is the right next step — or whether you should see a gastroenterologist first. We will say which.
