What causes red stool?

Red-colored stool typically refers to stool that appears red, which may be caused by conditions such as gastric ulcers, hemorrhoids, anal fissures, or bacterial enteritis.

1. Gastric Ulcer

Long-term consumption of irritating foods—such as chili peppers—or habitual intake of strong tea can irritate the gastric mucosa, leading to damage and rupture of mucosal blood vessels. This results in gastrointestinal bleeding; the blood then mixes with feces, causing red-colored stool.

2. Hemorrhoids

If the surface of the stool is coated with bright red blood, this may indicate bleeding from hemorrhoids. During difficult defecation, excessive straining or friction from hard stool against the hemorrhoidal tissue can cause bleeding, which is then passed along with the stool.

3. Anal Fissure

Constipation leading to hard, dry stools may cause tearing of the anal canal during defecation, resulting in bleeding. The blood adheres to the stool surface, giving it a red appearance, often accompanied by pain.

4. Bacterial Enteritis

Bacterial infection of the intestines triggers an inflammatory response. Prolonged inflammation damages the intestinal mucosa, causing rupture of superficial blood vessels and subsequent bleeding. The blood mixes with stool and is expelled together.