Gastrointestinal bleeding refers to bleeding that occurs anywhere in the digestive tract, from the mouth to the anus. It can manifest as bright red or dark-colored blood in vomit or stool. Causes include ulcers, inflammation, tumors, or blood vessel abnormalities. Symptoms may include abdominal pain, dizziness, fainting, or weakness. Urgent medical attention is necessary to identify and treat the underlying cause. Diagnostic tests such as endoscopy, colonoscopy, or imaging may be performed. Treatment depends on the cause and severity, ranging from medications to surgery. Prompt intervention is vital to prevent complications and restore gastrointestinal health.