Based on PubMed | Can lupus cause blood in the stool, and when should I seek medical attention for this symptom?

Blood in the stool can happen in people with lupus, although it is not among the most common symptoms, and it usually signals a problem in the gastrointestinal (GI) tract that deserves prompt medical evaluation. ^[1] Lupus can cause inflammation of blood vessels (vasculitis) in the intestines, which may lead to intestinal ischemia (reduced blood flow), ulceration, and bleeding, presenting as bright red blood (hematochezia) or dark stools. ^[2] In rare cases, severe colitis related to lupus vasculitis has caused massive lower GI bleeding and required urgent treatments or even surgery. ^[3] Small bowel bleeding tied to lupus mesenteric vasculitis has also been reported and may require interventional procedures to stop the bleeding. ^[4]

How lupus can lead to GI bleeding

• Lupus is a systemic autoimmune disease that can inflame tissues and organs throughout the body, including the GI tract. ^[1] When small blood vessels supplying the colon or rectum are affected (vasculitis), tissue injury and ulcers can occur, which may bleed. ^[2] Case reports document ischemic proctitis and colitis in active lupus, with rectal ulceration causing hematochezia that improved with high‑dose steroids once lupus activity was controlled. ^[2]
• Severe, diffuse ischemic colitis linked to lupus has, in rare situations, led to gangrenous changes and life‑threatening bleeding, highlighting the need for rapid diagnosis and treatment when symptoms escalate. ^[3]
• Bleeding can also arise from arteries outside the bowel, such as hepatic artery aneurysms associated with vasculitis, which may present as unexplained GI bleeding and require endovascular embolization. ^[5]

Other common causes to consider

Even in people with lupus, blood in stool is often due to causes not specific to lupus, such as hemorrhoids, anal fissures, diverticular bleeding, colon polyps or cancer, inflammatory bowel disease, intestinal infections, or medication‑related irritation. ^[6] Initial care focuses on stabilizing the person and identifying the source through a careful evaluation because the management depends on where and how fast the bleeding occurs. ^[6]

When to seek medical attention

• If you notice blood in your stool (bright red, maroon, or black tarry stools), you should seek medical care promptly because any GI bleeding can signal an underlying problem that needs attention. ^[7] Black, tarry stools (melena) often indicate bleeding from higher up in the GI tract and should be evaluated right away. ^[8]
• Call emergency services or seek urgent care if bleeding is significant and you have any signs of shock, such as rapid shallow breathing, dizziness or lightheadedness, fainting, confusion, cold clammy skin, or very low urine output. ^[9] Persistent or recurrent rectal bleeding also warrants immediate medical assessment to prevent complications. ^[10]

What to expect during evaluation

• Clinicians will first assess your vital signs and hydration and start intravenous fluids if needed to stabilize your circulation. ^[6] They will ask about the amount and color of blood, abdominal pain, recent medications (like NSAIDs, steroids, anticoagulants), and other symptoms to estimate risk and guide testing. ^[6]
• Depending on the suspected location, tests may include blood work (hemoglobin, platelets, coagulation), stool tests, and endoscopy (colonoscopy or upper endoscopy). ^[6] In cases where small bowel bleeding is suspected, additional imaging or specialized procedures may be used to locate and treat the source. ^[11]

Treatment approaches

• Management starts with resuscitation and stabilization, then targeted therapies such as endoscopic hemostasis, interventional radiology embolization, or surgery when necessary. ^[6] If lupus vasculitis is driving the bleeding, clinicians may use high‑dose corticosteroids and immunosuppressive medications to calm the inflammation and reduce the risk of ongoing tissue injury and bleeding. ^[2] Severe or refractory cases have required surgical intervention or endovascular treatments to control bleeding. ^{[3] [4]}
• If you are on medications that increase bleeding risk (for example, anticoagulants), your care team will review dosages and interactions; combination with high‑dose steroids can further raise GI bleeding risk and may prompt protective strategies such as acid‑suppression in select higher‑risk settings. ^{[12] [13]}

Practical tips for those with lupus

• Track any new GI symptoms (pain, cramping, diarrhea, dark or bloody stools), and share them quickly with your healthcare team because lupus activity can change over time and sometimes affects the gut. ^[1]
• Avoid non‑prescription NSAIDs unless your clinician approves, as they can irritate the GI lining and contribute to bleeding. ^[14] Maintain follow‑up with your rheumatology and gastroenterology teams so that lupus control and GI health are managed together. ^[15]
• If bleeding occurs, note the color and amount, any associated dizziness or fainting, and recent medication changes; these details help clinicians triage and treat effectively. ^[16]

Key takeaways

• Lupus can, in some cases, cause blood in the stool through intestinal vasculitis and ischemia, though this is relatively uncommon compared with other causes of GI bleeding. ^[2]
• Any visible blood in stool or black tarry stools should prompt timely medical evaluation, and significant bleeding with symptoms of shock is an emergency. ^{[7] [9]}
• Early stabilization and diagnostic workup are important, and if lupus inflammation is the driver, immunosuppressive therapy may be part of treatment alongside GI‑specific interventions. ^{[6] [2]}