If you have IBS, blood tests, faeces tests, and other examinations usually show normal values. So there is no “IBS test” that shows that you have IBS, but it is the symptoms you have that determine whether you get an IBS diagnosis or not.

However, to diagnose IBS, the doctor may perform a number of examinations and take samples to rule out that the symptoms are not caused by other diseases. So how is IBS diagnosed and what are its main causes?