Passing hard stools can irritate or tear the tissues lining your child's rectum and anus. There may be bright red streaks of blood on the surface of the stool or on diapers, underwear, or toilet tissue. This is not serious in children 6 months or older if there is only a small amount of blood and if bleeding stops occurring when the constipation is relieved.

In babies younger than 6 months, blood in the stool is more of a concern than in older children and adults. A visit to a health professional is needed immediately if there is more than a streak of blood on the surface of the stool or on the diaper. If there is more than a streak of blood, there may be bleeding in the digestive tract (gastrointestinal, or GI, tract).

If there is a bloody stool that looks like currant jelly, a visit to a doctor is needed immediately. This type of stool may indicate that a portion of the intestine has telescoped into another segment of the intestine (intussusception).

If your child has significant bleeding in the digestive tract, you will notice a moderate to large amount of blood in the child's stool (enough to leave a pinkish or red stain on the diaper or to turn the water in the toilet bowl red). This can be caused by inflammation, irritation, or infection.

Since blood acts as a laxative and an irritant, it will cause your child to pass any hard, dry stools that are in the digestive tract. Bowel movements will then become looser and more bloody. Depending on where the blood is coming from, usually in or below the stomach, and how quickly it is moving through the digestive tract, the blood may be bright red, reddish brown, black, or tarlike (tarry).