If you notice your poop is an abnormal color like green or black, it can be alarming. But what does it mean and what should you do? Here is a comprehensive guide to understanding the causes and treatments for green and black stool.
What Causes Green Poop?
Green poop is most commonly caused by diet and digestive issues. Possible causes include:
- Eating a lot of green leafy vegetables like spinach, kale, or broccoli
- Taking iron supplements or multivitamins with iron
- Food coloring or dyes
- Infection or inflammation in the intestines from conditions like Crohn’s disease or ulcerative colitis
- C. diff infection from antibiotics use
- Giardia parasitic infection
- Rotavirus infection
- Cancer in the bile ducts
- Rapid transit time of stool through the intestines
In most cases, green stool is harmless and simply reflects the foods you’ve eaten. But if it persists for more than a few days or occurs with other symptoms, it warrants seeing a doctor.
What Causes Black Poop?
Black or very dark poop can have several potential causes:
- Bleeding in the upper digestive tract from conditions like ulcers or cancer
- Iron supplements or bismuth medications (like Pepto Bismol)
- Eating black licorice, blueberries, black beans, or other dark foods
- Taking activated charcoal supplement
Black stool due to upper GI bleeding is considered a medical emergency. But black stool from foods or supplements is harmless.
When to See a Doctor
You should see a doctor if you have green or black stool along with any of these symptoms:
- Persistent diarrhea or constipation
- Blood in the stool
- Abdominal pain or cramping
- Nausea or vomiting
- Unexplained weight loss
- Fever
This can indicate a medical condition requiring treatment. Seek emergency care for very black, tarry stools, which may mean bleeding in the upper GI tract.
Medical Evaluation
To diagnose the cause of green or black stool, the doctor may:
- Ask about your symptoms and medical history
- Perform a physical exam
- Order lab tests on a stool sample
- Do imaging tests like x-rays, CT scan, or colonoscopy
- Refer you to a gastroenterologist for specialized care
Based on the evaluation, the doctor can determine if there is an underlying infection, inflammation, or other disorder causing the abnormal stool color.
Treatments
Treatment depends on the specific cause of green or black stool but may include:
- Dietary changes – avoiding foods that discolor stool if it is harmless. Adding fiber supplements if constipation is contributing.
- Medications – antibiotics for infections, steroids or other drugs for inflammatory bowel disease, iron supplements if anemia is causing green stool.
- Surgery – if there is GI bleeding, blockage, or cancer that requires surgical treatment.
- IV fluids and electrolyte replacement – if severe diarrhea is causing dehydration and electrolyte abnormalities.
Most causes of discolored stool are minor and resolve after treatment of the underlying problem. But significant bleeding or obstruction requires hospitalization and emergency care.
When to Seek Emergency Treatment
You need emergency care if you have black, tarry stools along with these symptoms:
- Lightheadedness
- Rapid heart rate
- Fainting
- Vomiting blood
This suggests severe GI bleeding and can be life-threatening without rapid treatment.
Other emergency symptoms include:
- Severe and constant abdominal pain
- High fever with stool changes
- Signs of dehydration like excessive thirst, dry mouth, and little urine output
- Sudden inability to have a bowel movement or pass gas
Obstruction, perforation, or severe infection in the digestive tract can all quickly become dangerous without emergency care.
Prevention
You may be able to reduce episodes of abnormal colored stool by:
- Drinking enough fluids
- Eating more fiber
- Avoiding foods that seem to cause symptoms
- Washing hands thoroughly before eating
- Finishing a full course of antibiotics if prescribed
Practicing good hygiene and having regular screening tests, like colonoscopy starting at age 45, can also help prevent some illnesses that cause greenish or black stool.
When to Worry
Green or black stool is usually not an emergency. In most cases you can see your doctor within 24-48 hours.
However, seek immediate medical attention if you have:
- Very black/tarry stools
- Vomiting blood
- Lightheadedness or rapid heart rate
- Fever over 101 F (38.3 C)
- Severe abdominal pain
- Inability to have a bowel movement or pass gas
These can indicate a life-threatening illness needing emergency treatment.
What to Expect from Your Doctor
Be prepared to answer these questions from your doctor:
- When did you first notice the abnormal stool color?
- What color is it – green, black, or something else?
- Do you see blood in or on the stool?
- Has your stool ever been this color before?
- Have you had any other symptoms like diarrhea, constipation, nausea, pain?
- What medications, supplements, or new foods have you had recently?
- Have you traveled out of the country recently?
- Do you use alcohol, tobacco, or recreational drugs?
- Do you have any chronic medical conditions or prior GI surgery?
- Is there any family history of GI disorders like IBD, polyps, or cancer?
Being honest and providing as many details as possible to your doctor will aid in determining the cause and getting you the appropriate treatment.
Coping with Green or Black Stool
Having green or black poop can be upsetting. Here are some tips for coping:
- Communicate openly with loved ones about your symptoms and worries
- Stay hydrated by drinking plenty of fluids
- Eat small, gentle meals until symptoms resolve
- Reduce stress through meditation, yoga, or deep breathing
- Keep a sense of humor and remember this will likely pass
- Listen to calming music or podcasts as a distraction
- Take over-the-counter anti-diarrhea or anti-nausea medication if needed
- Rest as much as possible until you feel better
Dealing with digestive issues can take an emotional toll. Make self-care a priority while waiting for your symptoms to improve.
Conclusion
Green or black poop will usually resolve itself, but can indicate a more serious problem. Pay attention to any accompanying symptoms and see a doctor if you have persistent or severe issues. With an accurate diagnosis, most causes of abnormal stool color can be successfully treated. Try not to worry, and focus on getting the care you need to feel better.