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Bloody Diarrhea Checker

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Bloody Diarrhea Symptoms

It is not uncommon, from time to time, to notice blood – even a small amount of bright red blood - in your stool. Typically, this is caused by conditions such as hemorrhoids (enlarged blood vessels in the rectum or anus) or anal fissures (tears or cracks in the tissue lining the anus or rectum).

Diarrhea is a common condition, experienced by most people, several times during their lives – most of the time, due to infection or from foods that disagree with you. Bloody diarrhea, on the other hand, is not common or normal, and requires professional medical care.

Bloody diarrhea may or may not be accompanied by nausea, vomiting, fever, chills, stomach pain, fatigue, severe anemia, dizziness, weakness, shortness of breath, chest pain, or headache.

Much of the time, bloody diarrhea is a sign of intestinal infection; sometimes, it can be an indication of a more serious condition, such as cancer or a vascular problem with your bowels. Let's look at the infections and non-infectious causes of bloody diarrhea.

Bloody Diarrhea Causes Overview

Infections:

  • Bacterial infections
  • Enterohemorrhagic Escherichia coli (EHEC) – There are many strains of the bacteria E. coli. Some strains of E. coli normally live in your intestines and do not cause illness. Some strains of E. coli can release shiga toxin and make you very sick with stomach pain, bloody diarrhea and even kidney failure.

    • Shigella
    • Campylobacter
    • Salmonella
  • Viral infections:

    • These are probably the most common infections to give you bloody stools and many viruses are capable of doing this, like Norovirus, Rotavirus and Adenovirus.
  • Parasitic infections

    • Infections with parasites like Entamoeba histolytica and Giardia Lamblia (common in hikers who drink water with beaver poop in it!) can lead to bloody diarrhea.

Serious non-infectious conditions:

  • Ischemic colitis – is a condition in which the blood flow to the large intestine is restricted. This may cause damage to your colon – damage severe enough to cause bloody diarrhea and even necrosis (death) of all or part of your colon. This is usually associated with severe abdominal pain and often occurs in people with a history of vascular disease elsewhere in the body.

  • Inflammatory Bowel Disease

    • Bloody diarrhea that is a result of a chronic disease process, such as inflammatory bowel disease (IBD), often lasts weeks or months and is associated with weight loss and feeling unwell. This can also cause you to lose blood and become anemic. Crohn's Disease and Ulcerative Colitis are the two most common types of IBD and both require the specialized care of a doctor called a gastroenterologist.
  • Colon cancer

    • Colon cancer can cause both diarrhea (which may or may not be bloody) and constipation. Other symptoms associated with colon cancer include a change in bowel habits, stomach pain, fatigue, weight loss and anemia.

Anal and rectal causes of bloody diarrhea:

  • Hemorrhoids are a common cause of blood on the toilet paper and on the outside of the stool, though they can also cause blood to be present in loose stools and diarrhea. Usually you will have pain, itching or even feel these near the anus.

  • Anal fissures can bleed and are usually associated with severe pain with bowel movements or pain after a bowel movement. This is a crack or tears in the anus and it can bleed, lead to blood on the toilet paper and in the stool.

Neither condition is life threatening, but both of these need medical care so you can feel better and not make these worse.

Top 10 Bloody Diarrhea Causes

  1. 1.Ulcerative Colitis

    Ulcerative Colitis (UC) is a condition that causes diarrhea, abdominal pain, and bloody bowel movements. These symptoms occur because the large intestine (colon) has become inflamed and acquired sores, known as “ulcers.”

    You should visit your primary care physician to discuss your symptoms. If the diagnosis is confirmed, treatment is likely to include medication as well as dietary and nutritional modifications.

    Rarity:
    Rare
    Top Symptoms:
    nausea or vomiting, diarrhea, fever, general abdominal pain, back pain
    Urgency:
    Primary care doctor
  2. 2.Colon Damage From Impaired Blood Flow

    A specific type of colon damage, called ischemic colitis occurs when blood flow to part of the large intestine (colon) is reduced due to narrowed or blocked blood vessels (arteries). The diminished blood flow provides insufficient oxygen for the cells in the digestive system. It can cause pain and can damage the colon. Ischemic colitis can affect any part of the colon, but most people experience pain on the left side of the belly area (abdomen). It is most common among people older than age 60. Commonly, ischemic colitis is misdiagnosed because it can easily be confused with other digestive problems.

    You should go to the ER immediately. Diagnosis is based on a doctor's physical exam, blood tests, and imaging. Treatment involves medication to treat or prevent infection or surgery if your colon has been damaged.

    Rarity:
    Rare
    Top Symptoms:
    abdominal pain (stomach ache), nausea, loss of appetite, diarrhea, being severely ill
    Urgency:
    Hospital emergency room
  3. 3.Crohn's Disease Flare

    Crohn's disease is a chronic inflammation of the digestive system. It is one of a group of diseases called inflammatory bowel disease. Crohn's can affect any area from the mouth to the anus, and may cause diarrhea and weight loss.

    You should speak with your primary care physician and/or gastroenterologist as soon as possible to determine if you have a flare.

    Rarity:
    Rare
    Top Symptoms:
    fatigue, nausea, stomach bloating, loss of appetite, abdominal cramps (stomach cramps)
    Urgency:
    In-person visit
  4. 4.New Onset Crohn's Disease

    Crohn's disease is a disorder caused by chronic inflammation in the digestive tract. The damaging inflammation causes abdominal pain, diarrhea, weight loss, and malnutrition.

    You should schedule an appointment with your primary care physician within a few days to start diagnostic tests and discuss if a referral to a specialist is needed.

    Rarity:
    Rare
    Top Symptoms:
    fatigue, stomach bloating, loss of appetite, constipation, abdominal cramps (stomach cramps)
    Urgency:
    Primary care doctor
  5. 5.Campylobacter Small Intestine Infection

    Infection with the Campylobacter bacterium is one of the leading causes of acute diarrhea worldwide. The risk for this infection is increased in people with HIV/AIDS.

    Seek care from a primary care physician as soon as possible. Treatment for diarrhea of bacterial origin involves rehydration as well as a course of antibiotics.

    Rarity:
    Rare
    Top Symptoms:
    diarrhea, abdominal cramps (stomach cramps), fever, general abdominal pain, severe diarrhea
    Symptoms that always occur with campylobacter small intestine infection:
    diarrhea
    Urgency:
    Primary care doctor

    Bloody Diarrhea Checker

    Take a quiz to find out why you’re having bloody diarrhea.

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  6. 6.Yersinia Intestinal Infection

    Yersinia enterocolitica is a bacterial foodborne illness. In most cases, the disease is caused by eating raw or undercooked pork.

    You should visit your primary care physician or an urgent care clinic as soon as possible to discuss these symptoms. It is likely an antibiotic will be needed.

    Rarity:
    Rare
    Top Symptoms:
    abdominal pain (stomach ache), diarrhea, being severely ill, fever, vomiting
    Urgency:
    Primary care doctor
  7. 7.Intestinal Infection With Ameba Parasite

    Visiting or living in places with poor sanitation can lead to parasite infections that can cause long-lasting diarrhea and stomach pain.

    You should go see a primary care physician (PCP) soon. Diagnosing parasite infections reuires stool samples at a PCP, and its treatment involves prescription anti-parasitic medications that a PCP would then prescribe.

    Rarity:
    Rare
    Top Symptoms:
    nausea, loss of appetite, diarrhea, constipation, chills
    Urgency:
    Primary care doctor
  8. 8.Shigella Infection

    Shigella infection is an acute bacterial infection caused by a group of bacteria called shigella. The infection affects the intestines and can be passed through direct contact with the bacteria in the stool.

    You can safely treat this condition on your own by replenishing your body with plenty of fluids. Avoid drugs intended to treat diarrhea, such as loperamide (Imodium) and diphenoxylate with atropine (Lomotil) because they can make your condition worse. If your symptoms do not improve, or worsen, make an appointment with your physician as treatment with antibiotics may be needed.

    Rarity:
    Rare
    Top Symptoms:
    diarrhea, general abdominal pain, fatigue, severe diarrhea, loss of appetite
    Symptoms that always occur with shigella infection:
    diarrhea
    Urgency:
    Self-treatment
  9. 9.Hemolytic Uremic Syndrome (Over 5)

    Hemolytic-uremic syndrome (HUS) is a disorder that usually occurs when an infection in the digestive system produces toxic substances that destroy red blood cells, causing kidney injury.

    You should seek immediate medical care at an ER, where blood tests may confirm the diagnosis. Treatment varies depending on severity of damage, but needs to be done as soon as possible. This is a life-threatening event!

    Rarity:
    Rare
    Top Symptoms:
    abdominal pain (stomach ache), fatigue, nausea, diarrhea, abdominal cramps (stomach cramps)
    Symptoms that always occur with hemolytic uremic syndrome (over 5):
    being severely ill
    Urgency:
    Hospital emergency room
  10. 10.E. Coli Infection

    EHEC, or Enterhemorrhagic Escherichia coli, is a strain of bacterium that can be acquired worldwide through eating contaminated food, especially undercooked ground beef, raw produce, or ready-to-eat cold meats. Contracting this type of bacterium may lead to bloody diarrhea and severe pain the abdomen.

    You should visit your physician or an urgent care clinic as soon as possible. This infection must be treated with prescription antibiotics and replacement of fluids lost by diarrhea.

    Rarity:
    Rare
    Top Symptoms:
    diarrhea, abdominal cramps (stomach cramps), being severely ill, fever, general abdominal pain
    Urgency:
    In-person visit

Bloody Diarrhea Treatments and Relief

You should seek immediate care for bloody diarrhea if you:

  • have had it for more than 24 hours
  • have diarrhea that is dark red or black
  • have severe abdominal pain
  • have signs of dehydration (dry mouth, dizziness, confusion, muscle cramping, excessive thirst)
  • have a fever (>100.4)
  • are over 65 years old
  • are pregnant
  • are currently or have recently finished taking a course of antibiotics

The treatment of bloody diarrhea requires addressing the underlying cause.

  • Avoid using anti-diarrheal medications such as loperamide or bismuth salicylate and diphenoxylate. These medications can complicate EHEC infections.
  • Stop taking any antibiotics.
  • Avoid NSAIDS (non-steroidal anti-inflammatory drugs such as ibuprofen), smoking, alcohol use, aspirin, anticoagulants, and anti-platelet agents.

As with any diarrhea, it is important to stay well hydrated and well nourished. It is equally important to replace electrolytes, especially sodium and potassium and this can be done with commercial sports beverages, bullion and fluids containing sodium and potassium.

FAQs About Bloody Diarrhea

Here are some frequently asked questions about bloody diarrhea.

What foods can cause blood in stool?

Only foods that contain a large amount of blood (blood sausage, blood pudding), foods that contain large amounts of heme (or the chemical in blood that holds oxygen), or foods that cause laceration to the bowel cause blood in the stool. Sharp items that are not food — glass, stones, metal — can lacerate the bowel causing blood in the stool. Other foods can cause ulcers in the GI tract. Foods that are very high in acid, or foods that cause "metaplasia" or changing of the structure of cells can over the long term, can lead to bleeding.

Can constipation cause blood in stool?

Constipation by itself does not cause blood in the stool. However, passing a particularly large stool may cause an anal fissure which usually presents with bright red blood on the tissue or in the toilet. If you have a history of hemorrhoids, passing hard stool can cause rupture of a hemorrhoid and dark red blood either on the stool or in the toilet. Finally, long term constipation can cause outpouchings of the intestines (diverticulosis) exposing blood vessels and causing dark red blood in the stool.

Can hemorrhoids cause bleeding in the stool?

Yes, hemorrhoids can cause bleeding either in the bowel, streaked on the feces, or on the toilet paper. Bleeding from hemorrhoids is usually painless and often happens sometime after a bowel movement but can be unprovoked. The blood may drip into the toilet and tinge the color of the water. Bleeding can also occur in large amounts which is worsened by straining.

Can certain antibiotics cause bloody diarrhea?

No. However, some antibiotics can alter the color of feces. Antibiotics do not affect the lining of the gut in such a way as to cause rupture. They may, however, cause cramping or bloating (from a lack gut mobility) or diarrhea from an increase in mobility. However, antibiotics can cause a form of infectious diarrhea, C. difficile, that infrequently may be associated with bleeding.

When should you see a doctor for bloody stool?

You should see a doctor if you are concerned about blood in your stool. You should visit the emergency room if there is a large amount of blood, if the blood is dark red or looks like coffee grounds or dark red sludge, or if you experience any lightheadedness, dizziness, or cold and clammy sensation or vomit blood.

Questions Your Doctor May Ask About Bloody Diarrhea

  • Q.Has your diarrhea gotten better or worse?
  • Q.How long has your diarrhea been going on?
  • Q.How many times have you had diarrhea in the last 24 hours?
  • Q.Any fever today or during the last week?

If you've answered yes to one or more of these questions, check our bloody diarrhea symptom checker.

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Bloody Diarrhea Symptom Checker Statistics

  • People who have experienced bloody diarrhea have also experienced:

    • 16% Abdominal Pain (Stomach Ache)
    • 8% Abdominal Cramps (Stomach Cramps)
    • 6% Nausea
  • People who have experienced bloody diarrhea had symptoms persist for:

    • 37% Less Than a Week
    • 35% Less Than a Day
    • 13% Over a Month
  • People who have experienced bloody diarrhea were most often matched with:

    • 15% Colon Damage From Impaired Blood Flow
    • 6% Ulcerative Colitis

Bloody Diarrhea Checker

Take a quiz to find out why you’re having bloody diarrhea.

Take a quiz