Blood tests detect abnormally high or low levels of substances in the blood that may indicate a variety of conditions, including digestive disorders or diseases. Traditionally performed in physician’s offices, laboratories and hospitals, they are useful tools for uncovering disorders in the human body.

Blood tests may be ordered for a number of reasons, including:

• Screening for a disease before signs and symptoms appear
  
  
• Helping determine a diagnosis
  
  
• Monitoring the progression of a disease
  
  
• Monitoring the effectiveness and safety of a patient’s treatment

Many digestive conditions involve blood tests in their diagnosis and treatment, in addition to other tests. One common blood test is a complete blood count (CBC), which measures the number of red blood cells, white blood cells and platelets in the blood. Other blood tests indicate the presence of certain antibodies, such as an antibody to the Helicobacter pylori bacteria, which can cause peptic ulcers.

Most blood tests require very little preparation beforehand.  Depending on the amount of blood required for the test, blood can be drawn from a vein, artery or skin puncture. Obtaining a blood sample only takes about five minutes, and most patients find blood tests to be nearly painless.