What does black stool mean in children, adults, in pregnancy?

What does black stool mean in children, adults, in pregnancy?
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Black stool as a symptom indicates bleeding in the digestive tract. However, it can also occur after eating certain foods or medications.

Black stool raises concern about blood in the stool. It can be a symptom of diseases of the digestive system.

Blood in the stool can be light bright red, darker red even with coagula (blood clots) to black - tarry.

Occasional blood in the stool occurs, for example, in haemorrhoids.
Diarrhoea with blood may indicate an inflammatory disease.
Hard stools in constipation are also a possibility.
Dark to black, usually in problems that are located in the higher parts of the bowel.

However, stools can be discolored for several reasons.

Is it really blood and will a home test be enough to detect it? Or is it better to contact a specialist?

In the case of diseases that disrupt or damage the mucous membrane of the digestive system, it is bleeding.

The blood is digested in the intestine, which then causes the typical dark, even black, tarry colour of the stool.

Black stools can also occur after the consumption of certain foods and medicines, in which case they are not the result of damage and disease of the digestive tract.

Changes in stool colour are important in terms of detecting the disease process. Therefore, it is not good to neglect them.

The emptying of stool (defecation) is a natural process during which the body gets rid of undigested and waste substances.

These are products of digestion, food residues, fatty substances, dead intestinal bacteria and mucosal cells.

The solid parts make up approximately 25%. The other 75% of the stool is water.

When defecating, it is important to note the consistency, colour, blood or odour of the stool, as well as the frequency and regularity of defecation.

For more information on stool, see the article:
Stool - what should we know about it?

If you want to know more about gastrointestinal bleeding and black stools, as well as non-digestive conditions, read on with us.

Black stools may be a symptom, but they also may not be...

As we mention in the introduction, stool discoloration can be influenced by disease, but also by other factors.

What affects stool characteristics:

  • Diet and fluid intake
  • eating habits
  • physical activity
  • colonisation of the gut by bacteria
  • medicines
  • stress

Some people defecate once or twice a day, but also after eating a large meal.

Another person has stools once or twice a week. Especially in old people, stools become thicker because of reduced fluid intake.

Constipation in the elderly is also a problem due to lack of exercise.

The problem may mark a disturbance in this regularity, the rhythm of defecation.

Let us now take a closer look at what influences the black coloration of the stool.

Black stools without GIT disease

It is not always necessary to look for a disease behind dark to black stools and thus worry unnecessarily about a serious illness.

GIT = gastro-intestinal tract = gastrointestinal system.

Influence of food

If the black stool is after food intake - it is not a sign of disease.

The colour is influenced by various foods, liquids, nutritional supplements and therefore natural or artificial (synthetically produced) food colourings.

Examples of foods that stain the stool a dark to black colour are:

  • Beetroot
  • blueberries
  • blackcurrants
  • spinach
  • red wine
  • liquorice
  • seaweed

Darker stools will be especially after a larger amount of this type of food has been taken or after drinking more fluids.

Alternatively, it may occur after taking animal charcoal.

Black stools when taking iron are common.

In some people, especially with anaemia and iron deficiency, the doctor will suggest and recommend iron supplementation with various supplements or medicines that contain iron.

In this case, black stools are a common manifestation of taking these preparations.

Similar is the case with medicines containing bismuth.

Therefore, in case of occurrence of black stools, it is necessary to recall the intake of food and nutritional supplements or medicines. After a few hours of discontinuation of such a diet, the stools will adjust.

If we cannot relate it to the dietary regimen, we need to look further.

The effect of medication

In addition to iron-containing preparations, dark to black stools may occur when taking medications that cause disruption of the wall of the digestive system and bleeding.

Examples of medications include:

  • acylpyrine - aspirin
  • non-steroidal anti-inflammatory drugs, antirheumatic drugs
  • anticoagulants (anti-clotting drugs), warfarin, heparin and others (in overdose)


Excessive alcohol intake or frequent drinking of coffee also has a negative effect on the mucous membrane of the tract. Bleeding from the oesophagus or stomach can also occur with repeated vomiting.

Bleeding and black stools after alcohol can also occur in a person who does not drink alcohol frequently and hard alcohol has caused him stomach inflammation and bleeding.

The mucous membrane in this part is stressed for a long time, which causes the formation of small cracks - erosions. At a later stage, a peptic ulcer may also develop in the site.

Bleeding stomach = haemorrhagic gastropathy - a swollen, bleeding stomach lining over a large area.

Stress and undue psychological strain as a negative

Caution, damage to the stomach lining can also be triggered by prolonged stress.

Black stools in diseases of the digestive system

Bleeding into the digestive tube can be health and life-threatening. It depends mainly on the provoking causes.

There are various acute or chronic conditions.

The presence of blood in the stool can be demonstrated in different ways. It mainly depends on the site of bleeding or the time period over which it occurred.

As a rule of thumb, the higher up in the digestive system the bleeding occurs, the darker to black the blood.

On the contrary...

Bleeding in the colon and rectum will show up as fresh blood. This can be darker with clots present, but also as fresh, bright red blood.

The blood may be mixed with the stool or only on the surface.

Alternatively, blood may be present only after stool and when cleaning the anal opening on toilet paper. This is usually the case with haemorrhoids or a tear in the anal opening.

The blood that comes from the upper areas before the small to large intestine is usually dark, black and poisonous. Bleeding can also be from the mouth or oesophagus.

On the other hand...

In bleeding from the terminal parts of the colon and rectum, it is fresh red. It is not digested.

What does blood in the stool look like?

What does a stool look like?

Melena black, tarry stool, in bleeding from the higher parts of the digestive tract
  • Black, tarry, colloidal stools that smell
  • occurs after approximately 8 hours due to intestinal bacteria, enzymes
  • if bleeding reaches approximately 50-100 ml or more of blood in 24 hours
  • melena is further divided into:
    • fresh melena - thin, black, greasy, colomose stools, as a sign of active bleeding and early sign of bleeding
    • old - emptying melena - black and dry stools, as a manifestation of older, already stopped bleeding
Enterorrhagia indicates the presence of fresh blood
  • it is bleeding from the colon and rectum
  • blood is mixed with stool
  • can also occur with massive bleeding from the small intestine, upper GIT (gastro-intestinal tract), stomach, for example in ulcer disease
  • or accelerated passage of blood through the intestine
  • mixed with faeces, or the blood itself passes without faeces
  • may be bright or dark red, with the presence of blood clots
Hematochezia presence of dark and light red blood, blood clots in the stool
  • also with bleeding from the colon, rectum and anal area
  • mostly from the left side of the colon
  • in English it is referred to as bright red blood per rectum (BRBPR)
  • dark, reddish-brown blood usually comes from the right side of the colon
Proctoragia bleeding from the rectum and anal area
  • bright red blood present
  • not mixed with stool
  • is on the surface of the stool
  • on the toilet paper during cleansing
Occult bleeding small bleeding invisible to the eye
  • chronic (long-term)
  • may be permanent or recurrent
  • can be detected with an occult bleeding test
  • occult = hidden bleeding
  • manifestations include anaemia, weakness, impaired breathing or repeated syncope, collapse
Obscure bleeding it is a present bleed visible externally, its source is unknown

In addition, vomiting of blood = haematemesis may also occur in upper gastrointestinal bleeding.

It is reported that most often black stools are a manifestation of ulcerative disease of the stomach and duodenum. An ulcer can also form on the lining of the oesophagus.

Read also our articles.

In the case of the esophagus, esophageal varices are dangerous. Similar to varicose veins of the lower limbs, this is an enlargement of the veins in the lining of the esophagus. Often the cause is liver enlargement and portal hypertension.

Alternatively, blood in the stool may also occur in gastritis. These may have different origins.

Inflammations of the intestine are also common. They can be non-specific, such as Crohn's disease and ulcerative colitis. The other side consists of various infectious bacterial(typhoid fever, listeriosis), viral or parasitic diseases.

The most serious ones are cancer of the oesophagus, stomach or oncological diseases of the small intestine.

What does black stool mean?

Some of the most common causes of bleeding:

  • Peptic ulcer - ulcer disease of the stomach and duodenum
  • erosive gastropathy
  • gastritis - inflammation of the stomach, also due to the intake of food, spices, alcohol, drugs
  • reflux esophagitis - inflammation of the oesophagus due to reflux of digestive juices from the stomach GERD
  • Mallory-Weiss syndrome - mainly after repeated and forceful vomiting, often after drinking alcohol, bleeding from longitudinal fissures in the oesophagus
  • oesophageal varices
  • angiectasis - vascular abnormalities of the GIT mucosa
  • Crohn's disease
  • Meckel's diverticulum
  • cancer
  • postradiation enteritis
  • aortoenteric fistula - pathological connection of the abdominal aorta and intestine
  • some other diseases
    • lupus erythematosus
    • infectious mononucleosis
    • haemophilia
    • disseminated intravascular coagulopathy (DIC)
    • haemolytic disease of the newborn
    • haemolytic anaemia
    • thrombocytopenia
    • thrombocytopathies
    • thrombocytopenic purpura
    • von Willebrand's disease
    • leukaemia
    • haemorrhagic fevers
    • liver disease and failure

Bleeding from the upper GIT is dangerous

An annual incidence of approximately 100-200 cases per 100,000 adult population has been reported.

The danger of upper GI bleeding stems from its acute course.

Haemodynamic instability and shock may occur in this type of bleeding due to circulatory failure following hemorrhage.

Pallor, weakness and fatigue, increased heart rate (tachycardia), low blood pressure, rapid breathing, sweating, dizziness and feeling faint, cold extremities, shortness of breath are associated.

Black stools in children

The first stool in newborns after birth is dark greenish-black. It is referred to as pitch. Later, the stool in the baby may be greenish-brown, dark and greenish.

Otherwise, as in adults, black stools are not natural in children and infants.

Dark to black stools in babies is a serious symptom. As the above diseases are rare in this period.

The influence of diet and the use of iron or black coal should be ruled out.

Read about stool in childhood.

If the child is markedly restless, cries, kicks his legs, has a large distended abdomen, vomits, and blood is present in the stool, immediate examination is necessary.

The article on the opposite problem is also interesting.

Light stools in childhood or adulthood may or may not indicate a health problem. In the more serious case, it is a liver or gallbladder disease. But you can learn more in the link to the article with the symptom in question.

Black and dark stools in pregnancy?

Pregnant women not infrequently add various food supplements, vitamins or minerals to their diet.

Therefore, in this context, it is necessary to consider the effect due to the added food and excess iron, including supplements containing it.

If the pregnant woman does not take any nutritional supplements, the occurrence of upper digestive system diseases is possible.

With the occurrence of black stools in pregnancy, it is necessary to think about:

  1. consider the discoloration of stools caused by the use of iron-containing tablets or nutritional supplements, which women usually take during the second and third trimesters
  2. rule out discolouration due to the consumption of certain foods or drinks
  3. neither of the previous options apply and this is not a one-off condition?
  4. a professional examination and a visit to the doctor
  5. during pregnancy, it is necessary to notice difficulties more intensively, especially as the body has to feed both the pregnant woman and the fetus, and may therefore be more susceptible to illness

Associated symptoms

If diet was not the cause, it is necessary to look elsewhere.

And especially if there are associated problems.

Examples of some associated symptoms:

  • blood visible in the stool
  • abdominal pain and cramps
  • distended abdomen
  • hard abdomen
  • weakness and fatigue
  • dizziness
  • fogginess and blackness before the eyes
  • increased body temperature to fever
  • diarrhoea
  • constipation
  • nausea and vomiting
  • vomiting, vomiting of blood
  • unexplained weight loss
  • pain on stool and painful urging to pass stool
  • chest pain and shortness of breath (dyspnoea)
  • later, behavioural and psychological changes, disorientation
  • disturbance of consciousness to unconsciousness and shock

When blood is present in the stool and when other problems are associated, it is necessary to seek professional examination.


A red or black colour in the stool alone does not immediately indicate that it is blood. In some cases, its presence is more difficult to recognise.

Therefore, it is better to contact a specialist.

The stool is examined, and it is examined for the presence of blood.

A well-known test is the faecal occult bleeding test, which detects the presence of blood in the stool even if it is not possible to observe it externally.

There is also a home test for occult bleeding available at the pharmacy, but even if it is positive, it may not immediately indicate a serious disease (oncological, inflammatory, etc.).
It is only a guide that can lead you to a doctor.
Blood in the stool can have different origins.

A medical history is important, supplemented by family history and the presence of cancer in the family.

A physical examination and assessment of vital signs are also performed. Blood loss is looked for (low blood pressure, increased pulse, rapid breathing, pale and cold skin, cold sweat, syncope).

The abdomen is examined by looking, palpating, tapping, listening. A per rectum examination is added.

Subsequently, endoscopic examination of the digestive tract, stomach (gastroscopy) is also chosen. It can confirm or refute diseases of the upper part of the GIT - the most common ulcer disease and others.

On the other side, anoscope and rectoscope examination can be used, and colonoscopy can look deeper into the colon.


The laboratory examination of the blood is important. The blood count (haemoglobin status, anaemia) and haemocoagulation (clotting status) form the basis. The blood group examination is also important, because of the need for blood transfusion in case of high blood loss. Other examinations are also carried out (blood sedimentation, iron tests, liver tests).

What does stool discoloration reveal? A number of diseases and symptoms

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The aim of the portal and content is not to replace professional examination. The content is for informational and non-binding purposes only, not advisory. In case of health problems, we recommend seeking professional help, visiting or contacting a doctor or pharmacist.