How are the causes of constipation or diarrhea diagnosed in gastroenterology?
With both constipation and diarrhea, you will first be asked to describe your symptoms and have a physical examination with your doctor. A blood test may also be ordered, but depending on whether you have constipation or diarrhea, your doctor will be looking for something different.
In cases of constipation, a blood test can reveal hormonal imbalances that may be causing the condition. Imaging tests (like x-ray or MRI) are also commonly used to evaluate a bowel obstruction. A colonoscopy, a colonic transit study, and tests that look at anal sphincter muscle function are other advanced tests that your doctor could prescribe in some situations.
In cases of diarrhea, a blood test can indicate whether an infection may be responsible. A stool test may then be used to identify the specific infection.