In most cases of gastroenteritis, you will not need a diagnosis from your GP because your symptoms should get better without any treatment.

If your symptoms persist or are severe, your GP may take a sample of your stools (faeces). This can be checked for the presence of specific bacteria or parasites. If a bacterium or parasite is identified, your GP can prescribe the most suitable antibiotic or anti-parasitic medication for your condition.

In some circumstances, blood and urine tests may be used to rule out other conditions, such as a urinary tract infection or pneumonia. This is normally recommended when your symptoms suggest that the infection is not limited to your digestive system. Such symptoms include:

• high temperature (fever) of 38ºC (100.4ºF) or above
• rapid heartbeat
• low blood pressure (hypotension)