What should you know about a FIT immunochemical test?

FIT uses antibodies that react with human blood from the lower digestive tract. A positive result does not diagnose cancer; blood can come from polyps, haemorrhoids, inflammation, or another bowel problem. A negative result lowers concern at that time but does not explain ongoing symptoms or replace advice about repeat screening.

Follow the collection instructions carefully, avoid contaminating the sample with urine or toilet water, and return it within the stated time. If the test is positive, arrange the follow-up your clinician recommends; this may involve a bowel examination such as colonoscopy. Tell the clinician about rectal bleeding, a change in bowel habit, weight loss, abdominal pain, or a family history of bowel disease. Learn more about [Colorectal Cancer Screening](/treatments/diagnostics-and-screening/colorectal-cancer-screening/).

Seek urgent medical help for heavy or continuing rectal bleeding, black tar-like stools, fainting, severe abdominal pain, or marked weakness. Contact a clinician promptly for repeated visible blood, persistent bowel changes, or symptoms that continue despite a negative FIT. People with [Ulcerative Colitis](/conditions/ulcerative-colitis/) may need a different monitoring plan.

Ask which collection method applies, when the result is expected, what a positive or negative result means for you, and whether your symptoms require assessment even if FIT is negative.