Diarrhea

Changes in bowel habits, such as diarrhea, are common problems for people with cancer. Diarrhea is the passing of loose, watery and frequent stools.

Causes

The most common cause of diarrhea in people with cancer is related to cancer treatments. The cells lining the gastrointestinal tract are rapidly dividing cells, so they can be easily damaged by treatments such as chemotherapy and radiation therapy. Diarrhea may be caused by:

• medicines
  • certain chemotherapy drugs, such as irinotecan (Camptosar, CPT-11), 5-fluorouracil (5-FU, Adrucil), methotrexate and docetaxel (Taxotere)
  • antibiotics
  • laxatives
• radiation therapy to the abdomen or pelvis, causing inflammation of the intestines (radiation enteritis)
• bone marrow or stem cell transplant, including graft-versus-host disease (GVHD)
• gastrointestinal surgery
• infection caused by bacteria, viruses, parasites or fungi
  • Clostridium difficile (C. difficile) is a bacteria that causes inflammation of the colon (colitis) and possible diarrhea following antibiotic therapy
• food sensitivity
• stress and anxiety
• fecal impaction – a large amount of dry, hard stool develops in the large intestine (bowel) because of constipation and there may be leakage of loose stool around the blockage

Symptoms

Along with loose, watery stools, a person may also have:

• gas (flatulence)
• abdominal cramping
• abdominal bloating

A person may have diarrhea during cancer treatment, at about 8 to 12 weeks after therapy, or it sometimes develops many months or years after treatment is finished.

Diagnosis

To help find out the cause of diarrhea, the doctor may:

• take a history of symptoms, bowel patterns, medications and treatments
• do a physical examination, including feeling the abdomen and doing a digital rectal examination to check for fecal impaction
• order tests such as:
  • stool tests to check for infection or blood in the stool
  • an abdominal x-ray
  • an endoscopy, such as colonoscopy

Prevention

There are many things a person can do to help prevent and cope with diarrhea:

• Eat small meals and snacks often throughout the day.
• Drink at least 8 to 10 glasses of fluid each day, preferably between meals, to replace lost fluids and help prevent dehydration. Choose non-carbonated, caffeine-free fluids such as water, juice, sports drinks and clear broth. Sports drinks, juices, broths and electrolyte replenishers (such as Gastrolyte) can help replace water and important salts (electrolytes) that are lost from the body during severe diarrhea. It's a good idea to dilute juice and sports drinks. They can increase diarrhea by drawing water into the bowel if they contain very high amounts of electrolytes and other substances.
• Avoid extremely hot or cold foods.
• Avoid caffeinated coffee, tea and alcohol, which can stimulate bowel activity.
• Limit greasy, fried, spicy or very sweet foods and beverages.
• Avoid sugarless gum and candies made with sugar alcohols (such as sorbitol or mannitol). They act like a laxative (make a person have a bowel movement).
• Stay away from foods that are natural laxatives, such as prunes, prune juice, rhubarb and papaya.
• Choose foods that contain less fibre or roughage. Foods that are high in fibre tend to increase diarrhea. White bread and pasta, white rice, cooked and canned fruit (with peel removed), cooked and canned vegetables, bananas, meat, poultry and fish are examples of foods that have little or no fibre.
• If diarrhea is severe, increase foods containing potassium, such as potatoes, bananas or melons.
• Avoid raw fruits and vegetables that are high in fibre or gas-forming, such as broccoli, corn, beans, cabbage, peas and cauliflower. Cooked vegetables may be easier to digest than raw ones. Peel fruit that has a skin, such as apples, before cooking.
• Avoid nuts, seeds, dried peas and beans.
• Avoid milk and milk products if they make diarrhea worse.
  • Lactose-intolerance can develop because of a deficiency in enzyme production (lactase), which is needed to digest milk and milk products. This can develop after intestinal surgery, radiation to the lower abdomen or chemotherapy. It can result in cramping, bloating and diarrhea.
  • Try lactose-reduced milk or milk products.
  • Buttermilk or yogurt can be eaten, because the lactose in them has already been broken down (digested).
  • If very lactose-intolerant, try an over-the-counter product like Lactaid, which contains lactase or ask to speak to a registered dietitian.

Management

Tell the doctor if you have diarrhea and if it continues for more than 24 hours, causes abdominal pain or cramping. Keep a record of the number, amount and appearance of bowel movements for the doctor. The healthcare team will try to determine the cause of diarrhea and take measures to treat it. Do not use over-the-counter medications without checking with the doctor first.

The healthcare team may suggest trying a clear liquid diet to give bowels time to rest. Anti-diarrhea medications may be prescribed, such as:

• Kaopectate
• loperamide (Imodium)
• diphenoxylate and atropine (Lomotil)
• octreotide (Sandostatin, Sandostatin LAR) – for severe diarrhea

Intravenous fluids may be needed to replace lost water and nutrients if diarrhea does not improve. Gradually include low-fibre foods once diarrhea goes away. A regular diet may be resumed if there are no further episodes of diarrhea.