Rectal bleeding, medically termed hematochezia, is the passage of fresh, bright red blood from the anus and is a common gastrointestinal symptom. Blood in the stool can also appear as melena—a dark, black, and tarry stool—which indicates bleeding higher up in the digestive tract. While the cause is often minor, any instance of rectal bleeding requires a medical evaluation to determine the source and confirm a diagnosis, as it can signal a serious underlying condition.
Understanding the Causes and Recognizing Emergency Signs
Bleeding from the rectum often originates from the lower gastrointestinal tract, near the anus, resulting in bright red, fresh blood. The most frequent causes are benign conditions related to the anal canal, such as hemorrhoids and anal fissures. Hemorrhoids are swollen veins, and anal fissures are small tears in the anal lining, both commonly caused by straining or passing hard stools.
Less common, but more serious, causes include diverticular disease, which involves small, bleeding pouches forming in the colon wall. Bleeding can also be a symptom of inflammatory bowel diseases (IBD) like Crohn’s disease or ulcerative colitis, which cause chronic inflammation and ulceration. Colorectal polyps, growths on the lining of the colon, may also bleed. These are of concern because certain types can become cancerous.
While many cases are minor, certain signs indicate a medical emergency requiring immediate attention. A large volume of blood in the toilet bowl, especially with blood clots, suggests significant blood loss. Signs of shock or instability, such as sudden dizziness, fainting, or a rapid heart rate, signal that the body needs urgent care.
Melena, the black, sticky, and foul-smelling stool, indicates bleeding likely originating from the upper gastrointestinal tract, such as the stomach or small intestine. This darker color results from the blood being partially digested as it travels. Bleeding accompanied by severe abdominal pain, a high fever, or an inability to pass a bowel movement should also prompt an immediate emergency visit.
Immediate Home Management and Lifestyle Adjustments
For minor bleeding associated with common causes like fissures or hemorrhoids, immediate adjustments to diet and routine can help manage symptoms while awaiting a medical appointment. Increasing fiber intake is effective, aiming for approximately 28 grams per day, depending on age and sex. Fiber-rich foods, such as whole grains, legumes, apples, and pears, help to bulk and soften stool.
Adequate hydration is equally important; drinking eight to ten glasses of water or non-caffeinated fluids daily helps fiber work efficiently to prevent hard stools. Soft stools pass more easily, reducing straining and allowing existing hemorrhoids or fissures to heal. Over-the-counter stool softeners can be used temporarily to make bowel movements less painful by drawing water into the stool. Laxatives should generally be avoided as they can cause diarrhea and further irritation.
Symptom relief can be achieved through a warm sitz bath, where the lower body is soaked in a few inches of warm water for 15 to 20 minutes, two or three times daily. This practice helps increase blood flow to the anal area, promoting healing, and relaxes the muscles to ease pain and irritation. Adding Epsom salts may provide additional temporary relief.
Applying a topical astringent like witch hazel with a cotton pad can help reduce swelling, itching, and burning sensations. Simple over-the-counter creams or suppositories containing hydrocortisone or lidocaine can soothe inflammation and numb pain. It is beneficial to avoid prolonged sitting on the toilet, which puts excessive pressure on the anal veins, and to avoid straining during a bowel movement.
When and How Doctors Diagnose and Treat Rectal Bleeding
Seeking professional medical evaluation is necessary for any instance of rectal bleeding to rule out serious conditions. The diagnostic process typically begins with a physical examination, including a digital rectal exam (DRE). The doctor inserts a lubricated finger into the rectum to check for masses, tenderness, or internal hemorrhoids. This is often followed by an anoscopy, which uses a small, lighted tube to visualize the anal canal and lower rectum.
If the bleeding source is not immediately apparent, or if the patient has risk factors like advanced age or a family history of colon cancer, further endoscopic procedures are indicated. A flexible sigmoidoscopy examines the rectum and the lower part of the colon using a flexible scope. The standard for a full evaluation is a colonoscopy, which allows the doctor to view the entire length of the colon and remove any polyps found during the procedure.
Treatment depends on the cause identified during the diagnostic workup. For hemorrhoids that do not respond to home care, minimally invasive procedures can be performed, such as rubber band ligation, which involves placing a small band around the base of the hemorrhoid to cut off its blood supply. Prescription topical medications, including higher-strength corticosteroid creams or calcium channel blocker ointments, may be prescribed for persistent fissures or proctitis.
In cases of severe, non-resolving hemorrhoids or complex anal fissures, a surgical procedure may be necessary, such as a hemorrhoidectomy or a lateral internal sphincterotomy. Bleeding from other sources, like inflammatory bowel disease or diverticulosis, is managed with disease-specific treatments, including anti-inflammatory drugs or antibiotics. For identified polyps, removal during a colonoscopy is the definitive treatment to prevent the potential development of cancer.