Last updated March 14, 2022

Management of Patients With Acute Lower Gastrointestinal Bleeding



A focused history, physical examination, and laboratory evaluation should be obtained at the time of patient presentation to assess the severity of bleeding and its possible location and etiology. Initial patient assessment and hemodynamic resuscitation should be performed simultaneously. (Strong  “We recommend”Very low)
Hematochezia associated with hemodynamic instability may be indicative of an UGIB source, and an upper endoscopy should be performed. A nasogastric aspirate/lavage may be used to assess a possible upper GI source if suspicion of UGIB is moderate. (Strong  “We recommend”Low)
Risk assessment and stratification should be performed to help distinguish patients at high- and low-risk of adverse outcomes and assist in patient triage including the timing of colonoscopy and the level of care. (Conditional (weak)  “We suggest”Low)

Hemodynamic resuscitation

Patients with hemodynamic instability and/or suspected ongoing bleeding should receive intravenous fluid resuscitation with the goal of normalization of blood pressure and heart rate before endoscopic evaluation/intervention. (Strong  “We recommend”Very low)
Packed red blood cells (RBCs) should be transfused to maintain the hemoglobin above 7 g/dl. A threshold of 9 g/dl should be considered in patients with massive bleeding, significant comorbid illness (especially cardiovascular ischemia), or a possible delay in receiving therapeutic interventions. (Conditional (weak)  “We suggest”Low)

Management of coagulation defects

Endoscopic hemostasis may be considered in patients with an international normalized ratio (INR) of 1.5–2.5 before or concomitant with the administration of reversal agents. Reversal agents should be considered before endoscopy in patients with an INR >2.5. (Conditional (weak)  “We suggest”Very low)
Platelet transfusion should be considered to maintain a platelet count of 50 × 109/l in patients with severe bleeding and those requiring endoscopic hemostasis. (Conditional (weak)  “We suggest”Very low)
Platelet and plasma transfusions should be considered in patients who receive massive RBC transfusion. (Conditional (weak)  “We suggest”Very low)
In patients on anticoagulant agents, a multidisciplinary approach (e.g., hematology, cardiology, neurology, and gastroenterology) should be used when deciding whether to discontinue medications or use reversal agents to balance the risk of ongoing bleeding with the risk of thromboembolic events. (Strong  “We recommend”Very low)


Colonoscopy should be the initial diagnostic procedure for nearly all patients presenting with acute LGIB. (Strong  “We recommend”Low)
The colonic mucosa should be carefully inspected during both colonoscope insertion and withdrawal, with aggressive attempts made to wash residual stool and blood in order to identify the bleeding site. The endoscopist should also intubate the terminal ileum to rule out proximal blood suggestive of a small bowel lesion. (Conditional (weak)  “We suggest”Very low)

Bowel preparation

Once the patient is hemodynamically stable, colonoscopy should be performed after adequate colon cleansing. Four to six liters of a polyethylene glycol-based solution or the equivalent should be administered over 3–4 h until the rectal effluent is clear of blood and stool. Unprepped colonoscopy/sigmoidoscopy is not recommended. (Strong  “We recommend”Low)
A nasogastric tube can be considered to facilitate colon preparation in high-risk patients with ongoing bleeding who are intolerant to oral intake and are at low risk of aspiration. (Conditional (weak)  “We suggest”Low)


In patients with high-risk clinical features and signs or symptoms of ongoing bleeding, a rapid bowel purge should be initiated following hemodynamic resuscitation, and a colonoscopy performed within 24 h of patient presentation after adequate colon preparation to potentially improve diagnostic and therapeutic yield. (Conditional (weak)  “We suggest”Low)
In patients without high-risk clinical features or serious comorbid disease or those with high-risk clinical features without signs or symptoms of ongoing bleeding, colonoscopy should be performed next available after a colon purge. (Conditional (weak)  “We suggest”Low)

Endoscopic hemostasis therapy

Endoscopic therapy should be provided to patients with high-risk endoscopic stigmata of bleeding: active bleeding (spurting and oozing); non-bleeding visible vessel; or adherent clot. (Strong  “We recommend”Low)
Diverticular bleeding: through-the-scope endoscopic clips are recommended as clips may be safer in the colon than contact thermal therapy and are generally easier to perform than band ligation particularly for right-sided colon lesions. (Conditional (weak)  “We suggest”Low)
Angioectasia bleeding: noncontact thermal therapy using argon plasma coagulation is recommended. (Conditional (weak)  “We suggest”Low)
Post-polypectomy bleeding: mechanical (clip) or contact thermal therapy, with or without the combined use of dilute epinephrine injection, is recommended. (Strong  “We recommend”Very low)
Epinephrine injection therapy (1:10,000 or 1:20,000 dilution with saline) can be used to gain initial control of an active bleeding lesion and improve visualization but should be used in combination with a second hemostasis modality including mechanical or contact thermal therapy to achieve definitive hemostasis. (Strong  “We recommend”Very low)

Repeat colonoscopy for early recurrent bleeding

Repeat colonoscopy, with endoscopic hemostasis if indicated, should be considered for patients with evidence of recurrent bleeding. (Strong  “We recommend”Very low)


A surgical consultation should be requested in patients with high-risk clinical features and ongoing bleeding. In general, surgery for acute LGIB should be considered after other therapeutic options have failed and should take into consideration the extent and success of prior bleeding control measures, severity and source of bleeding, and the level of comorbid disease. It is important to very carefully localize the source of bleeding whenever possible before surgical resection to avoid continued or recurrent bleeding from an unresected culprit lesion. (Conditional (weak)  “We suggest”Very low)
Radiographic interventions should be considered in patients with high-risk clinical features and ongoing bleeding who have a negative upper endoscopy and do not respond adequately to hemodynamic resuscitation efforts and are therefore unlikely to tolerate bowel preparation and urgent colonoscopy. (Strong  “We recommend”Very low)
If a diagnostic test is desired for localization of the bleeding site before angiography, computed tomographic (CT) angiography should be considered. (Conditional (weak)  “We suggest”Very low)


Non-aspirin NSAID use should be avoided in patients with a history of acute LGIB particularly if secondary to diverticulosis or angioectasia. (Strong  “We recommend”Low)
In patients with established high-risk cardiovascular disease and a history of LGIB, aspirin used for secondary prevention should not be discontinued. Aspirin for primary prevention of cardiovascular events should be avoided in most patients with LGIB. (Strong  “We recommend”Low)
In patients on dual antiplatelet therapy or monotherapy with non-aspirin antiplatelet agents (thienopyridine), non-aspirin antiplatelet therapy should be resumed as soon as possible and at least within 7 days based on multidisciplinary assessment of cardiovascular and GI risk and the adequacy of endoscopic therapy (as above, aspirin use should not be discontinued). However, dual antiplatelet therapy should not be discontinued in patients with an acute coronary syndrome within the past 90 days or coronary stenting within the past 30 days. (Strong  “We recommend”Low)

Recommendation Grading



Management of Patients With Acute Lower Gastrointestinal Bleeding

Authoring Organization

Publication Month/Year

April 1, 2016

Document Type


External Publication Status


Country of Publication


Document Objectives

This guideline provides recommendations for the management of patients with acute overt lower gastrointestinal bleeding. 

Target Patient Population

Patients with acute overt lower gastrointestinal bleeding

Inclusion Criteria

Female, Male, Adolescent, Adult, Older adult

Health Care Settings

Ambulatory, Emergency care, Hospital, Outpatient

Intended Users

Nurse, nurse practitioner, physician, physician assistant


Assessment and screening, Diagnosis, Prevention, Management, Treatment

Diseases/Conditions (MeSH)

D016099 - Endoscopy, Gastrointestinal, D005767 - Gastrointestinal Diseases, D006471 - Gastrointestinal Hemorrhage, D041741 - Lower Gastrointestinal Tract


endoscopy, bleeding, gastrointestinal

Source Citation

Strate, Lisa L MD, MPH, FACG; Gralnek, Ian M MD, MSHS. ACG Clinical Guideline: Management of Patients With Acute Lower Gastrointestinal Bleeding, American Journal of Gastroenterology: April 2016 - Volume 111 - Issue 4 - p 459-474 doi: 10.1038/ajg.2016.41


Number of Source Documents
Literature Search Start Date
January 1, 1968
Literature Search End Date
March 2, 2015