Constipation In Stomach Cancer

Constipation in Stomach Cancer is actually very common. There are many reasons for this and I will teach you how to relieve your symptoms as well as explaining why this can become an issue.

So, why do you become constipated?

Well the 3 main ways it occurs are due to either the disease itself, the drugs used in managing symptoms or in people that already have coexistent symptoms.

The Disease Itself

Ascites and Constipation

Stomach cancer can spread to the abdominal cavity and liver initially. When this happens certain problems can arise.

These include the formation of ascites, a form of fluid in your abdomen and this can occur in large amounts.

If this occurs, the fluid can compress the bowel wall and result in constipation

Tumor Producing Excessive Calcium In Blood

Tumors have lots of different functions and one of these is producing an abnormal hormone known as PTH-like hormone.

This causes a rise in your bodies serum calcium levels which can make you thirsty, make you want to pass more urine, cause dehydration and has other effects including mood changes and constipation.

If your cancer spreads to your bones, the bone can release excessive calcium too producing the same effects.

Lack of Fiber Intake

One common issue in stomach cancer is the inability to take in large amounts of food and fluid. Our bodies require fiber to bulk up stools and if you don’t get this in your diet problems can ensue.

General food intake is also an issue until corrective measures such as surgery or chemotherapy are used.

Most people believe that not eating causes their constipation, but whilst this may be true to an extent, you should still be able to have a bowel motion.

Drugs Used In Managing Symptoms

Drugs that are commonly used in managing symptoms, particularly painkillers can cause constipation in stomach cancer patients.

The main culprits for this are the opiate medicines given to you such as codeine phosphate, morphine and diamorphine.

Coexistent Symptoms

You mustn’t forget constipation is an issue for many people and not only when you have cancer. It is estimated that 12 to 14% of the world’s population suffer from the condition.

So, a cancer sufferer may already suffer from symptoms prior to developing the disease

There are many complex issues with this including psychology, diet, pre-existing bowel conditions and many more.

Why Is Preventing Constipation In Stomach Cancer So Important?

Preventing constipation is very important as it can increase the likelihood of fluid and food build up in your stomach.

If this happens, you are more likely to vomit and reducing this may help to improve your symptoms as well as your digestion.

In the post operative period constipation in stomach cancer patients can be a similar issue and preventing straining is very important.

However, diarrhea is also common post-operatively and your surgeon and oncologist should advise at this time.

How Can I Relieve My Constipation?

Well, there is no easy answer when it comes to constipation in stomach cancer. The reason for this is that the usual advice of diet and exercise may not be possible for a sufferer.

However, there are still way’s to manage your symptoms and I will go through these here for you:


Dietary modifications are difficult, but the most important factor is insuring an adequate amount of fiber is obtained from your diet.

There are 2 forms of fiber – soluble and insoluble.  The former seems the most sensible one to increase in your diet as it is can be taken as a liquid, particularly if taken as a smoothie.

The main soluble fibers are:

List of Soluble Fiber Foods





Nectarines and Peaches






Black Eyed Peas

Chick Peas



Brussel Sprouts

Whilst you might not think of the vegetables as being easy to take, they too can be liquidised for you to take.

Fiber Supplements

There are many fiber supplements on the market that can be taken to ease constipation.

The most notable ones are Metamucil and Benefiber although there are others available on the market.

These can be dissolved in water or juice and drank or can be sprinkled on your food.

Drugs For Constipation

There are many laxatives available to treat your constipation. The most commonly used ones include:

Bulking agents

Bulking agents as the name suggest bulk up your stools. They draw water in to the stool making it softer and bulky.

An example of these are Sterculia (Normacol) and Ispaghula husk (Fybogel), both natural products that are available in powder form that you can reconstitute in water and drink.

Another example is Methylcellulose which can be taken as granules. There are tablets, but these are quite bulky although you can crush them.

These are good starting laxatives as they are quite gentle on your bowel.

Stimulant Laxatives

These stimulate your bowel to contract by irritation. Examples of these include senna, a natural laxative from the Senna pod and Bisacodyl.

Senna is available as a liquid preparation and Bisacodyl as a tiny tablet.

Osmotic laxative

Osmotic laxatives work by drawing water in to your stool. If your stools are very hard, this may be an option for you and are often used in combination with bulking agents.

The commonly used ones are Lactulose and Polyethylene Glycol (Movicol, Mirolax, Glycolax). Lactulose is very sweet and comes as a syrup that can cause quite a lot of wind in some people.

Glycerin suppositories are another example and have the advantage of not needing to be swallowed. They will only work though if your stools are in the rectum or lower bowel.

Magnesium based laxatives are quite good in treating constipation in stomach cancer patients and something I often recommend. Examples are Magnesium Citrate and Magnesium Hydroxide (Milk of Magnesia) and Magnesium Sulphate which is found in Epsom salts.

There are other forms of laxative that come as enema’s, but these are best advised by your own doctor.

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