Wondering if you actually have IBS? Use this self-diagnosis table! Sources and table from my big IBS post.
Note that the more of these conditions that you have, the more likely the diagnosis is. So, if you take the first example, an obese smoker on prednisone with constipation is more likely to have diverticulitis than a skinny non-smoker with diarrhea.
Also, please note that I’ve italicized the most important parts of a diagnosis. For example, unexplained weight loss is a pretty big warning sign for colon cancer and Chron’s. If you just have diarrhea and don’t have unexplained weight loss, neither colon cancer or Crohn’s are likely (but they’re still possible).
IBS Diagnosis Table
|If you have||Or if you are||Then you might have|
|Bloating OR constipation OR diarrhea OR bright blood in your stool||Obese OR a smoker OR a user of anti-inflammatories/steroids||Diverticulitis|
|Constipation OR diarrhea OR unexplained weight loss OR fatigue||Over the age of 45 (especially over the age of 65) OR have a history of cancer||Colon cancer|
|Bloody diarrhea||Ulcerative colitis|
|Diarrhea OR unexplained anemia OR fever OR unexplained weight loss OR growth retardation||Crohn’s disease|
|Joint pain OR cold intolerance OR constipationOR depression OR heavy menstrual flow OR unexplained weight gain or fatigue OR hair loss||Female||Hypothyroidism|
|Diarrhea AND nausea OR vomiting OR weight loss||In an area with poor water quality or food hygiene standards||Giardia|
|Abdominal bloating OR gas OR distension OR diarrhea||A user of proton pump inhibitors (e.g. Prilosec) OR opioids OR gastric bypass OR colectomy||Small intestinal bacterial overgrowth (SIBO)|
|Diarrhea OR bloating OR fatigue OR anemia OR unexplained blisters (dermatitis herpetiformis)||Type 1 diabetic||Celiac disease|
|Diarrhea||Bile acid malabsorption|
|Constipation||Over 65 OR African American OR pregnant/a mother||Dyssnergic defecation|
|Abdominal pain and bloating OR gas OR watery stool following the ingestion of foods containing lactose||Black, Latino, or Asian||Lactose intolerance|
|Diarrhea OR constipation OR brain fog OR joint/muscle pain, OR skin rash/dermatitis||Female OR in the third to fourth decade of life||Non celiac gluten sensitivity|
|Nausea and vomiting OR feeling of fullness or burning in your stomach OR blood in your vomit or stool.||In an area with poor water quality or food hygiene standards||H. pylori|
|Constipation OR diarrhea OR nausea OR a feeling of early fullness||A motility disorder, like slow transit constipation|
|**RARE CONDITIONS FOLLOW BELOW (you probably don’t have these)**|
|Constipation since early childhood||Hirschsprung’s disease|
|Chronic or intermittent watery diarrhea OR unexplained weight loss, OR joint pain||Over 65 OR female||Microscopic colitis|
|Flushing OR diarrhea OR shortness of breath OR palpitation||Carcinoid syndrome (part of carcinoid tumors)|
|Nausea OR vomiting, OR diarrhea OR anemia OR weight loss||Eosinophilic gastroenteritis|