Blood in stool is not always visible. Small amounts of bleeding from the bowel can stay hidden (occult) for a long time. Finding it early matters, because early bowel cancer often causes no symptoms at all.
Why hidden blood matters
Most bowel cancers develop slowly from benign growths called polyps. Bleeding from a polyp or tumour can be one of the first signs. The risk of bowel cancer rises with age and increases significantly from the age of 50.
Blood in stool does not always mean cancer. More common and less serious causes include haemorrhoids, an anal fissure, polyps, stomach ulcers, gum disease and some medicines such as aspirin or anti-inflammatory painkillers.
Bowel cancer warning signs
- a change in your poo that is not usual for you – softer, diarrhoea or constipation
- needing to poo more or less often than usual
- blood in your poo (red or black) or bleeding from your bottom
- often feeling you need to poo, even just after going
- tummy pain, bloating or a lump in your tummy
- losing weight without trying
- feeling very tired or short of breath (signs of anaemia)
What a FOB test detects
A faecal occult blood (FOB) test looks for traces of blood in a stool sample that you cannot see with the eye. Bleeding from a tumour can come and go and may be unevenly spread in the stool, so take the sample exactly as the leaflet says, from different parts of the stool, and repeat the test if advised.
The Testera FOB Rapid Test for Occult Blood checks a small stool sample for hidden blood at home.
FOB Rapid Test for Occult Blood – €6.49 →
What the result means
- Positive: blood was found and the cause needs to be checked. See your family doctor. You will usually be referred for a colonoscopy – a camera examination of the bowel. A positive result does not mean you have cancer.
- Negative: no blood was found in this sample. It does not completely rule out bowel cancer or polyps. If you have symptoms, see a doctor anyway.
National screening in the Baltics
Lithuania, Latvia and Estonia run national bowel cancer screening programmes for certain age groups. In Lithuania and Latvia, men and women aged 50–74 can take a free occult blood test every two years – ask your family doctor about taking part (in Latvia no invitation letter is sent, so there is no need to wait for one). In Estonia, men and women aged 56–68 born in the years set for the current round are invited every two years through their family health centre. A home rapid test does not replace the national programme – if you are invited, take part.
See a doctor if
- you have any of the bowel cancer warning signs above
- your FOB test is positive
- someone in your close family has had bowel cancer
Get urgent medical help if your poo is black or dark red, or you have bloody diarrhoea. Call 112 if you are bleeding non-stop from your bottom or pass a lot of blood or large clots.
Common questions
Does a positive FOB test mean I have bowel cancer?
No. It means blood was found and the cause needs to be checked. Often it is something less serious, such as haemorrhoids or polyps. A colonoscopy will show the cause.
Can I use a home test instead of national screening?
No. If you are in the screening age group, take part in the national programme. A home test can be an extra check, for example if you are outside the screening age or between invitations.
Can haemorrhoids cause a positive result?
Yes. Haemorrhoids, an anal fissure and bleeding gums can all add blood to the stool. That is why any positive result should be assessed by a doctor.
Rapid tests are intended for preliminary screening and do not replace a doctor’s consultation.
Sources: NHS – bowel cancer symptoms, NHS – bowel cancer screening, Tervisekassa