Constipation as a Side Effect of Cancer Treatments
Constipation is usually defined as having difficult or less frequent bowel movements than what’s normal for you. Cancer treatment, including pain and some anti-nausea medications, can lead to constipation. Other factors that can reduce bowel activity include a decrease in fiber and fluid intake and a decline in activity, such as may occur from fatigue.
If you’re unable to have a bowel movement after three days, be sure to consult with your physician, particularly if you see blood in your stool, laxatives are not helping, you have abdominal cramps, and/or you’re experiencing severe vomiting.
Like diarrhea, constipation can have many causes. It can be a complication of the cancer itself (for example, the cancer may have caused a bowel obstruction) or of cancer treatment. One of the most common treatments that can lead to constipation is narcotic analgesics (such as opioids), which are used to control cancer-related pain.
In general, because it’s far easier to prevent severe constipation before it occurs than to manage the problem after it develops, if you observe a change in your normal bowel habits, you should talk to your healthcare team.
Numerous steps can be taken to help get the bowels going, including the following:
Drinking plenty of fluid: Fluids help soften the stool and make it easier to pass through your gut. Water is the fluid of choice. On occasion, you can try a senna tea (such as Smooth Moves tea), as long as your oncologist approves.
If you do use senna tea, be sure not to overuse it. In some cases, dependency can occur and you’ll require senna to have a bowel movement. Follow the directions on the package label.
Eating plenty of fiber: Insoluble fiber has a laxative-like effect and speeds up the passage of food and waste through your digestive tract. Whole grains, especially whole wheat, are good sources of this fiber. Vegetables, beans, fruits, and dried fruit are also great sources. Remember to slowly increase your intake of fiber to decrease the chance of gas and bloating.
Trying warm prune juice: Prune juice contains a natural laxative. Try drinking 4 ounces of prune juice at the time of day that you normally have a bowel movement.
Adding ground flax meal or wheat bran to your foods: These can be added to cooked cereals, salads, yogurt, and muffins to boost your fiber intake. Start with 1 tablespoon per day, and increase up to 3 tablespoons throughout the day as tolerated. Take any oral medications an hour or two before or after consuming flax meal to avoid interfering with their absorption.
Drink plenty of water and other fluids when you increase your fiber intake, because fiber draws water into your digestive tract.
Being active: Physical activity can stimulate bowel movements. If your doctor approves, try getting at least 30 minutes of activity most days of the week. You can achieve this just by taking leisurely walks.
Eating yogurt and kefir: The probiotics or good bacteria in these foods can help keep your gut healthy and promote normal bowel movements. Aim for two to three servings per day, if possible.
If you’re experiencing constipation, talk with your healthcare team. They may recommend over-the-counter medications such as stool softeners or gentle stimulants.
If constipation persists and you also experience nausea and vomiting, contact your doctor and healthcare team. Some cancers can cause a blockage of the digestive tract. If this happens, you may be advised not to eat too much fiber or foods like flax meal and wheat bran, or you may be told not to eat anything at all for a while.