If you notice that your poop is black or tarry, it may be due to a simple change in your diet or a new medication you are taking.
However, it could also be a sign of a medical issue that you shouldn’t ignore. It is always recommended that you contact your doctor if you experience black, tarry stools.
Iron supplements are one of the common causes of black poop. These pills are often prescribed for anemia, a condition where there are not enough red blood cells to transport oxygen around the body. Iron supplements can also cause other side effects, such as stomach aches, constipation, nausea, and heartburn. If you experience any problems after taking iron supplements, contact your doctor to discuss alternative options.
Eating certain dark-colored foods can also turn your poop black. These foods include black licorice, chocolate sandwich cookies, blueberries, grape juice, and beets. The color of your poop should return to normal once you stop eating these foods.
Medications containing bismuth, such as Pepto-Bismol and Kaopectate, can also turn your poop black. While this symptom is harmless, you should stop taking the medication and contact your doctor if you experience a ringing or buzzing sound in your ears, become deaf, or feel worse.
A bleeding ulcer is the most concerning cause of dark stools. An ulcer is an open sore in your stomach or small intestine that can bleed, causing dark and tarry poop. Alcohol and NSAIDs, as well as H. pylori, increase your risk of developing gastric ulcers. Other signs of an ulcer include burning pain in your stomach, a swollen belly, burping, heartburn, nausea, vomiting, or vomit that looks like coffee grounds. If you experience any of these symptoms, contact your doctor immediately.
There are medications available for ulcers that can lower the amount of acid in your stomach or protect it from further damage. If you experience any of the following symptoms, call your doctor right away: blood in your poop or vomit, difficulty breathing, feeling like you are about to pass out, losing weight without trying, or loss of appetite.
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Esophageal and Gastric Cancers
If you have bleeding in the upper GI tract — the esophagus, stomach, and duodenum — you could have black, tarry stools that are called melena. It could be a sign of esophageal and gastric cancers.
Some other symptoms of esophageal cancer are:
- Problems with swallowing
- Losing weight when you aren’t trying to
- Pain in your chest
- Indigestion or heartburn
- Coughing
If you have gastric (stomach) cancer, you could have symptoms like:
- Feeling tired
- Being bloated after you eat
- Severe heartburn or indigestion
- Nausea or vomiting
- Pain in your stomach
- Losing weight when you’re not trying to
Treatment for these cancers depends on the stage of the disease and how far it’s spread. Options can include surgery, chemotherapy, or radiation.
Mallory-Weiss Tear
Intense coughing or vomiting can tear the esophagus and make it bleed, a condition called a Mallory-Weiss tear.
Other symptoms you might get are:
- Bright red vomit or black stuff in your vomit that looks black like coffee grounds
- Weakness
- Dizziness or fainting
- Trouble breathing
- Pale skin
- Diarrhea
- Belly or chest pain
Most tears heal on their own. If yours doesn’t, your doctor can use a heat treatment or give you medicine to stop the bleeding.
Call your doctor if you:
- See a dark color in your vomit or poop
- Feel weak or dizzy
- Feel short of breath
- Have pain in your chest or belly
Esophageal Varices
Varices are swollen veins in the esophagus — the tube that your food travels down to get from your throat to your stomach. These abnormal veins can sometimes leak blood or break open. They’re more common in people with liver disease.
If varices are the cause of bright red blood in your stools, you might also have symptoms like: