The saliva test, called Endotest, is already being used in an NHS pilot study, and Endosure – a bowel electrical signal test – is part of a clinical trial at Worcestershire Acute Hospitals NHS Trust.
Before this bowel test, women fast for six to eight hours and then drink water for 45 minutes.
The new draft guidance means GPs will be able to start offering both to some patients, if available. Not every GP will have access immediately and use should be supervised by a healthcare professional experienced in diagnosing and treating endometriosis.
The NHS will continue to collect evidence on how well these tests work.
Neither are intended to be used as stand-alone diagnostic tests, but should mean women receive diagnosis and treatment much more quickly.
Currently, the main way to diagnose whether a patient has the disease on the NHS is through a surgical procedure called laparoscopy, under general anesthesia.
Emma Cox, chief executive of Endometriosis UK, welcomed the tests, adding: “The availability of these new tests must go hand in hand with training for GPs and nurse practitioners to ensure quick access to those who need them and end pain and underrecognition of symptoms.”