Professor Bjarnason takes an individualized broad based holistic approach to each patient. When a diagnosis has been made he aims to provide first class treatment for all Gastroenterological diseases by conventional means as dictated by evidence based medicine. However when this is ineffectual (such as may be the case in patients with the Irritable Bowel Syndrome) then he does not hesitate to try unconventional treatments such as wheat free diets (effective for bloating in IBS), mold free diets (effective for the "intestinal candida syndrome"), etc. In the most resistant cases he has established a sound collaboration with medically trained homeopaths.

In the forefront of investigating and treating IBD -
ulcerative colitis and Crohn's disease.
The methods that Professor Bjarnason has developed (measurement of intestinal permeability and inflammation) allow fast, accurate and non-invasive diagnostic discrimination between patients with the Irritable Bowel Syndrome (IBS) and Inflammatory Bowel Disease (IBD).
These investigations allow assessment on the prognosis of inflammatory bowel disease that are instrumental in deciding whether medical or surgical treatment is in the patient’s best interest.
With these comprehensive tests come the most accurate clinical predictors of IBD relapse, thus allowing interventional medical treatment at a stage where there are minimal side-effects.  When surgery is the best option, close professional collaboration with the expertise of minimally invasive surgeons, ensures maximum safety and speed of recovery.
Professor Bjarnason treats patients with active Crohn s disease and ulcerative colitis by established methods (such as 5-aminosalicylic acid, prednisolone, azathioprine (or 6-Mercaptopurine), elemental diets (and other dietary regimes), antibiotics, cyclosporine, surgery, etc. as appropriate for the severity of the disease). He has a particular expertise in treating patients with active Crohn’s disease with elemental diets (having been instrumental in establishing its efficacy and mode of action) and the new anti-cytokines or so called biological treatments.
For those who are concerned about the side effect of treatment there is the option of white cell apheresis (removal) namely "Adacolumn" treatment. This treatment selectively removes certain white cells from the circulation by filtering the blood through a column and it is without any major side effects. The Professor has one of the greatest experience in Europe in treating patients with Adacolumn™ (White cell apheresis/removal). __Adacolumn™ is particularly attractive and effective in all stages of ulcerative colitis (and in many patients with Crohn's disease). Recent studies show that it can be used effectively in prventing clinical relapse of patients with IBD who are at significant risk.

Latest medical technology – Innovative, proven practice
Professor Bjarnason is internationally known for his research (inventing, developing and validating) non-invasive methods that allow accurate assessment of intestinal function. A recent addition to this is the use of wireless capsule enteroscopy. This is a new investigation that allows clinicians to obtain a video picture of the whole of the small bowel, in a non-invasive manner. This technique is superceding conventional radiology for the detection of small bowel disease, such as obscure gastrointestinal bleeding, Crohn's disease or the side effects of NSAIDs – (the so-called non-steroidal anti-inflammatory drugs) thus facilitating the detection of disease where none was thought to exist. __With pinpoint detection of abnormality allows biopsies for diagnosis (balloon aided small bowel flexible enteroscopy).  The Professor is in the forefront of wireless capsule enteroscopy research having published widely on the subject as well as being an author of chapters in textbooks and atlases.

Professor Bjarnason has developed a number of non-invasive small bowel tests that are uniquely helpful for the differential diagnosis of various intestinal diseases. These include tests of intestinal permeability, intestinal sugar metabolism (disaccharidases), malabsorbption, bile acid-induced diarrhoea, intestinal inflammation, pancreatic function, etc.

Colorectal cancer
Colorectal cancer is the 2nd and 3rd most common cancer in men and women, respectively and is a common cause of cancer related mortality. The prognosis of colorectal cancer has not changed appreciably in the last few decades. The best hope for reducing mortality and improving prognosis is to diagnose the cancer at an early asymptomatic stage (when surgery is associated with a 85% 5 year survival, as opposed to less than 20% for more advanced lesions) or to detect precancerous lesions such as large colonic polyps that can be removed during colonoscopy.
Professor Bjarnason is a highly skilled and competent colonoscopist.
However for those who are concerned (with minimal symptoms or symptoms that are not particularly suggestive colorectal cancer or those with a family history of the disease) about the invasiveness of the procedure can be offered non-invasive screening tests for colorectal cancer. Currently the most sensitive one is the faecal calprotectin test with a sensitivity in excess of 90% for detecting any stage of the disease (early or advanced disease). The test also detects most of the larger (more than 1 cm) colorectal polyps (that confer the greatest risk of cancer transformation). A normal faecal calprotectin test result in subjects with average risk of the disease provides good to excellent assurance that a colonoscopy is not indicated. There are other tests available that are more specific but less sensitive for the detection of colorectal cancer. The tests can be repeated at 6 to 12 month intervals for reassurance. A positive test of course is an indication for colonoscopy in most subjects. _
In the event that colorectal cancer is found the Professor works within a multidisciplinary team of experts that use state of the art equipment to stage the disease, a dedicated team of colorectal surgeons that have international reputation for their expertise in minimally invasive surgery, hepatobiliary surgeons (in the case of solitary liver metastasis) as well as experts in oncology and radiotherapy thus ensuring the best possible treatment and prognosis.

Irritable Bowel Syndrome
The irritable bowel syndrome accounts for over 40% of all Gastroenterological consultations and has a prevalence in the community of at lease 20%. It is a diagnosis made by the exclusion of "organic" intestinal disease which can be made in many patients without reverting to invasive tests.
Professor Bjarnason aims to provide first class treatment for all Gastroenterological disease by conventional means as dictated by evidence based medicine. For the irritable bowel syndrome he would always implement appropriate dietary treatment for constipation-diarrhoea, consider the use of anti-spasmodics, anti-diarrhoeal agents, questran, low dose antidepressants, etc. However these treatments are famed for their lack of efficacy.
In these circumstances a holistic approach is made as well as a biomedical one. This may involve cognitive treatment and/or hypnotherapy (both are of proven efficacy in certain sub-types of the irritable bowel syndrome) or in more resistant cases eradication regimes for intestinal Candida albicance and/or a major dietary intervention treatment such as food exclusion diets or elemental diets (for up to 6 weeks followed by serial re-introduction of food in order to detect food intolerances), gluten, yeast and/or starch free diets and food exclusion regimens in close collaboration with dieticians to ensure nutritional adequacy during the treatment. This treatment is not only helpful in some patients with problematic irritable bowel syndrome but efficacy is also suggested in patients with rheumatic diseases including fibromyalgia, post-viral fatigue syndrome, various immune deficiency syndromes and of course food allergy and intolerance.

Solid research leading to innovative treatment
One of the most recent research findings is that that the bacterium Helicobacter pylori which is the main culprit in the development of gastric and duodenal ulcers as well as stomach cancer has a detrimental effect on patients with Parkinson’s disease. Successful eradication treatment of Helicobacter pylori appears to reverse many of the features of Parkinson’s disease and indeed the evidence is that this alters the natural history of the disease. Patients with Parkinson’s disease will be assessed by a multi-disciplinary team which includes clinical neuro-pharmacologists,  specialised Parkinson’s disease nurse, etc. in order to optimize treatment and treatment success.