What causes constipation?
Constipation can be caused by the chemo drugs themselves, changes in lifestyle or other medications prescribed during cancer treatment including:
- Drugs used to treat nausea and vomiting
- Decreased activity and bed rest
- Pain medications
- Elevated calcium level in the blood (hypercalcemia of malignancy)
- Thyroid problems
- Diet changes
- And even stress
What are the symptoms
Constipation means that you are not able to open your bowels as regularly as normal and it can become very uncomfortable and even painful.
You may experience abdominal cramping, a sense of fullness in the abdomen, a stomach which is hard to the touch or rectal pain. But the symptoms are not always obvious – you may experience a loss of appetite and a vague feeling of being unwell, symptoms that are common to cancer.
What can you do?
During your cancer treatment it is advisable to keep a medication and side effect diary. If you start to notice changes, add your bowel movements. It’s important to keep track so that if you need to consult your medical team, you can tell them exactly what you are experiencing.
Speak with them before taking any ‘over the counter medications’ such as laxatives, enemas, or suppositories. They will offer advice on changes to your diet, lifestyle and the kind of medication you may need.
Below are some ‘home help’ suggestions you can try to relieve or even prevent constipation in the first place:
- Drink lots of fluids - many patients will find relief by simply increasing the amount of fluids they drink. Drink at least 2 litres per day. Stick to water and juice – avoiding drinks that contain caffeine, soda or coffee because they can cause dehydration, which could make your constipation worse.
- Eat more fiber - for mild cases of constipation, increasing fiber in the diet can be all the body needs for regular bowel movements. But check with your doctor first – it may not be advisable for patients who have had a bowel obstruction or bowel surgery.
Nuts, bran, vegetables, legumes, sweet potatoes whole wheat breads and pasta, brown rice, and many fruits and vegetables are all high-fiber foods. Or you could try old-age natural dietary remedies for constipation. These include prune juice, prunes, fig syrup and dried apricots.
It's important to be aware that eating more fiber may initially increase discomfort until the constipation has been relieved.
- Get some exercise – Even when undergoing treatment, it’s still very important to keep moving. Something as simple as going for a short, regular walk can help to prevent and relieve constipation. For those who are bedridden, moving from a chair to the bed can help because it utilizes the abdominal muscles. But be sure to talk it over with your medical team – they will be able to recommend exercises and tell you just how much you should do.
What types of medication are available?
As mentioned earlier, before taking anything, talk to your medical team and get their recommendations. Some work better than others depending on what’s causing your constipation, but some have the potential to interfere with chemotherapy drugs – so check first.
For instance, with some chemotherapy regimens, the combination of drugs, especially drugs to prevent nausea, are very constipating. In this case, your oncologist may subscribe something to prevent constipation in the first place - it’s often a lot easier to prevent than to treat severe symptoms. Different types of medication include:
- Bulk-forming laxatives - These medications work to draw water back into the intestine to decrease the hardness of the stool, as well as by decreasing transit time—the amount of time that stool stays in the colon. An example of this category is Metamucil (psyllium).
- Stimulant laxatives - Stimulants work directly on the nerves around the colon to stimulate transit of stool through the gastrointestinal tract. Since it can be painful when very hard stools pass through the colon, these are often given along with a stool softener. Examples of stimulant laxatives include Senekot (senna) and Dulcolax (bisacodyl).
- Osmotic laxatives - Osmotic laxatives work to keep fluids in the colon and also stimulate peristalsis—the rhythmic contractions of the colon that move stool forward. Examples include Chronulac (lactulose), glycerin suppositories, Miralax (polyethylene glycol), magnesium citrate and Milk of Magnesia (magnesium hydroxide).
- Emollients/Stool softeners - Stool softeners soften the stool by working with the mix of water and fat in the stool. These medications soften the stool but do not decrease transit time, so they are often used along with another medication to facilitate a bowel movement if these have become infrequent. An example of these is Colace (docusate).
- Lubricants - These medications bring water into the stool to soften it and also lubricate the stool for passage out of the body. Mineral oil is an example.
In extreme cases, where faecal impaction occurs, and the stools become very hard and dry, you may need manual removal of stool using gloved fingers. Not something anyone would relish, so please take extra special care to ensure you drink enough water, take the right amount of fiber and take any medication recommended by your doctor.
If you’ve had experience of chemo related constipation and have any advice to offer members of the Facebook Chemotherapy Support Group, please request to join the group. You’ll find lots of friendly people offering support and advise on anything and everything to do with their experiences of cancer and chemotherapy.