Merck Manual

Please confirm that you are a health care professional

Differentiation of Small-Intestinal from Large-Intestinal Diarrhea

Differentiation of Small-Intestinal from Large-Intestinal Diarrhea

Clinical Sign

Small Intestine

Large Intestine

Frequency of defecation

Normal or slightly increased

Very frequent

Fecal volume

Normal to increased

Decreased

Urgency

Absent

Usually present

Tenesmus

Absent

Usually present

Mucus in feces

Usually absent

Frequent

Blood in feces

Dark black (melena)

Red (fresh)

Weight loss

May be present

Rare