UrgentEmergency Guide
Rectal bleeding: Red Flags & Emergency Signs
Rectal bleeding in any patient over 45, or with change in bowel habit, unexplained weight loss, or anaemia, warrants urgent colonoscopy to exclude colorectal cancer.
🚨 Call 999 / 112 Immediately
- ⚠Massive rectal bleeding with haemodynamic instability — lower GI haemorrhage, 999
- ⚠Rectal bleeding with abdominal pain, fever, and peritonism — ischaemic colitis or perforation
⚡ See a Doctor Today
- •Rectal bleeding mixed with stool (not just surface) — blood coming from higher up
- •Rectal bleeding with change in stool calibre — colorectal cancer
- •Rectal bleeding with iron-deficiency anaemia without explanation
High-Risk Combinations
When rectal bleeding occurs together with any of these symptoms, urgency increases significantly:
Conditions to Rule Out Urgently
Colorectal Cancerurgent
FIT test + colonoscopy; 2-week wait referral if positive
Ischaemic Colitisurgent
CT abdomen; colonoscopy; vascular/surgical review
Severe IBD Flareurgent
Mayo score; IV steroids; gastroenterology admission
Condition Authority Pages
Differential diagnosis analyses:
When to Call Emergency Services
- →Large bleed with dizziness, pallor, or low blood pressure