What should you know about black loose stool causes?
Updated

Short answer
Black loose stool may be coloured by food or medicines, but black tarry stool can indicate upper digestive bleeding and should receive prompt medical assessment.
This answers one question. It is not a diagnosis and does not replace an assessment by a licensed doctor.
At a glance
- Record
- Timing, texture, smell, medicines, and recent foods
- Do not ignore
- Unexplained black tarry stool or faintness
Possible explanations
Loose stool moves through the bowel faster than formed stool. Iron and bismuth-containing medicines can make it black, while foods with deep colouring can do the same for a short time. Black, sticky, foul-smelling stool may instead be melaena, formed when blood is digested in the stomach or upper small intestine. Gastritis and peptic ulcer disease can cause bleeding in that area. Helicobacter pylori infection can contribute to irritation and ulcer formation. Colour and looseness do not identify the cause alone, so associated symptoms and recent exposures matter.
Steps to take
Write down when the stool changed, whether it is sticky or watery, and any new food, supplement, or medicine. Sip fluids if you can drink normally, especially after repeated loose stools. Contact a healthcare professional promptly if the black colour is unexplained, persists, or has a tar-like quality. Mention anti-inflammatory pain medicines, stomach symptoms, prior ulcers, and any recent treatment for Helicobacter pylori infection. Do not stop prescribed medicines without advice.
Urgent symptoms
Seek emergency care for black loose stool with fainting, worsening light-headedness, marked weakness, confusion, breathlessness, severe abdominal pain, or vomiting blood. Urgent help is also needed when repeated stool loss prevents drinking, urine becomes unusually scarce, or you cannot stay awake normally. These features may point to bleeding or significant fluid loss. If weakness or dizziness is present, avoid driving and ask another person to stay with you while help is arranged.
Questions to bring
Could my medicine or food explain the colour? Does this sound like melaena? Should I be evaluated for gastritis, peptic ulcer disease, or Helicobacter pylori infection? What fluid replacement is appropriate for me?
Find care
General Clinics & Polyclinics in Dubai
That answer is general. If you want it applied to your own case, these are licensed general clinics & polyclinics listed in Dubai.
The Court Residence, 39B Street, Jumeirah 1, Dubai
Accepts: Tabby, Tamara
Elite Business Bay Residence - Shop 03 & 04, 34 Marasi Dr - Business Bay - Dubai - United Arab Emirates
Accepts: Tabby
Airport View Building, Al Garhoud, Dubai
Accepts: Daman, Thiqa, AXA, Cigna +25 more
IBIS Building, 5th Floor, Unit 5003, Deira, Dubai
Accepts: AXA, Cigna, MetLife, Allianz Care +18 more
Ordered by verification status and how complete each clinic's public record is, then alphabetically. This is a directory listing, not a ranking — Zavis does not rate or recommend providers.
A factual listing drawn from the UAE health regulators' public licence registers. It is not a referral, an endorsement, or advice that any of these providers is right for you.
Questions people ask
Can loose stool become black from iron?
Iron can darken stool, but black sticky stool or symptoms such as weakness still need prompt medical advice.
When is black loose stool an emergency?
Treat it as an emergency when it occurs with fainting, severe weakness, confusion, vomiting blood, or severe abdominal pain.
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Medical disclaimer. This page is general health information, not medical advice, and it cannot diagnose you. Always consult a licensed healthcare provider about your own symptoms and treatment. In an emergency in the UAE, call 998 for an ambulance.