Side Effects

Overview

• Constipation is the infrequent or difficult passing of hard, dry stool.
• There are many causes of constipation, such as:
  • Drinking less water
  • Eating fewer foods with fiber
  • Less exercise
  • Taking medications such as pain medications and iron supplements
• If you are constipated, you may feel bloated, have cramps and not eat well enough to keep up your weight (a key goal of cancer treatment).
• This handout explains some of the causes of constipation. It also covers self‑care and treatment options.

Causes

Pain Medication

Many of the medicines used for pain control slow the gastrointestinal (GI) tract. This may cause constipation. Ask your healthcare team if your medicine puts you at risk. It is important to control pain, so take pain medicines as needed. However, you may want to begin stool softeners or laxatives to prevent constipation. Stool softeners hold water in the stool to keep it soft.

Laxatives stimulate movement through the GI tract. A medicine that has both a laxative and a softener is senna with docusate (Senokot‑S). You do not need a prescription for this. It is available in most grocery and drugstores. You can safely take up to eight Senokot-S pills per day. Start with one tablet, two times a day or as directed by your healthcare team. Gradually increase the dosage until you have soft-formed stools on a regular basis. However, do not take more than eight tablets per day.

Decreased Activity

Many people feel tired and do not move around as much during chemotherapy (chemo) treatment. This slows down the GI tract. Be as active as you can. The movement of walking stimulates the GI tract.

Poor Oral intake

If chemo causes nausea or vomiting, you may not be able to eat and drink as much as normal. This can cause constipation.

Ask your healthcare team for tips to manage nausea and vomiting.

General Tips

• A food plan high in fiber helps normal stools, and it adds to and softens the stools. The best way to get more fiber is by eating more fruits, veggies, legumes and whole grains. The goal is to eat 25 to 35 grams of fiber per day.
• You should drink at least 2‑3 liters of fluid per day. Try warm prune juice or warm nectar at bedtime and/or in the morning. Getting enough liquid helps keep stools soft. If your urine is dark, you are not drinking enough.
• Eat small, frequent meals.
• Drink warm or hot fluid (including soups). This stimulates the GI tract.
• Light exercise, such as walking, will help start the passage of stools.
• Try to stick to a steady and daily bathroom schedule.
• Include bran in your meals by adding it to cereals, casseroles, applesauce, and so on.
• You may want to try natural stool softeners, such as Metamucil.
• Slowly include high‑fiber foods into your food plan. At first you may feel cramping and swelling, but these will go away once your body adapts to the high fiber.
• Avoid those foods that worsen constipation; for instance, some find cheese constipating.
• Limit your intake of food and drink that cause gas or bloating. This may help your comfort. Examples are fizzy drinks and cabbage.

High‑Fiber Food Plan

Add fiber to your diet every day unless you have been told to limit fiber.

Hi‑Fiber Foods (Get As Much As You Can):

Breads, Cereals and Grains (four or more servings) : Whole‑grain products such as breads, rolls, bagels, muffins, crackers, rice, pasta, bran cereals, granola and oatmeal.

Fruit (at least two servings) : Fresh fruits with skin and seeds, dried fruits, prune juice, nectars and fruit juice with pulp.

Veggies (at least two servings) : Raw veggies, corn, potato with skin and cooked veggies with skins or stalks.

Animal and Dairy Products, and Protein Choices: Cooked, dried beans, peas and lentils and chunky peanut butter.

Lower‑Fiber Foods(Minimize)

Breads, Cereals and Grains (four or more servings) : Processed, white and refined bread and grains such as Italian bread, French bread and white rice.

Fruit (at least two servings) : All fruit juices without the pulp, and canned fruits.

Veggies (at least two servings) : Vegetable juices and canned veggies.

Animal and Dairy Products, and Protein Choices : Blended and pureed meats.

Self‑Care

• Keep track of your BMs. Treat constipation right away when symptoms first appear. Do not wait to take action.
• Fiber supplements: It may be difficult to meet daily fiber needs with food alone. For instance, one apple with skin has 4 grams of fiber, bran flakes have 5 grams. Ask about fiber supplements from your healthcare team.
• Adding medicinal fiber too fast to your diet may cause cramping and bloating. To prevent this, gradually add fiber in 1 teaspoon increments every five days.
• Do not ignore the urge to have a BM. Holding stool results in harder and larger stool that is more difficult to pass.
• If you have fewer than 3 BMs per week, you may drink 4 ounces of prune juice at room temperature. Then immediately drink a hot liquid. Contact your healthcare team for further guidance if needed.
• Do not use enemas and suppositories if your platelet or white blood cell counts are low or if you are taking blood thinners.

Report to Your Doctor…

• If you go three days without a BM.
• If you had constipation for several days followed by diarrhea. This might indicate an impaction (severe constipation) which needs attention.
• If there is blood in the stool.
• If you have cramps or vomiting that does not stop.
• You may benefit from a visit with a dietitian. Ask for a referral.
• There are medications your doctor may order or suggest for you to use. Be sure to check with your doctor before starting any over‑the-counter medications or home cures.

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GI Side Effects