Do What You Can to Ease Side Effects of Treatment and Symptoms of Colorectal Cancer

Each treatment option has its own set of side effects. You should talk with your doctor about what to expect with your treatment. You can also ask for your doctor’s help in dealing with side effects. In this section we discuss the most common side effects that people have while they are being treated for colorectal cancer.

It’s also important to remember that your cancer can have both a physical and a mental effect on you. Talk with your doctor about how your cancer is making you feel. There are things you and your healthcare team can do together to deal with issues such as pain, anxiety, and depression. When you deal with those issues, your quality of life should improve, and it will be easier to achieve a positive attitude. A positive attitude will help you in your fight against cancer.

Here is a list of the most common side effects people have from the treatments for colorectal cancer. These side effects are usually temporary and do not normally cause serious problems if they are addressed.

  • Anxiety and depression

  • Bladder damage (frequent urination, or pain or bleeding while urinating)

  • Diarrhea

  • Fatigue

  • Low platelet count, as noted from blood tests

  • Mouth sores

  • Nausea or vomiting

  • Pain

  • Reduced white-blood-cell count, as noted from blood tests

  • Skin irritation

Learn tips for how to cope with these side effects below.

With some treatments, there is a chance of more long-term side effects. You should talk about these issues with your doctor, especially if you have rectal cancer.

  • Early menopause

  • Vaginal changes

  • Sexual dysfunction

  • Lower sperm count

Anxiety and Depression

Many people feel blue, anxious, or distressed after being told they have cancer. These feelings may continue or come back throughout treatment.

Taking these actions may ease your mental stress.

  • Talk to your family or friends.

  • Consider joining a cancer support group or finding a cancer “buddy” who can help you cope.

  • Ask your doctor for a referral to a social worker, psychologist, or psychiatrist.

Bladder Damage

Bladder damage is possible with radiation therapy. This could lead to bladder spasms and frequent, urgent, or burning urination. Your doctor can prescribe medication to prevent spasms. Drinking more liquids during your treatment period will also help prevent these kinds of problems.

Bleeding or Bruising

Throughout your treatment, your doctor will take small samples of your blood for testing. One thing he or she is checking is your number of platelets. Without enough platelets, your blood may have difficulty clotting. You may bleed or bruise easily. Although it is rare that a platelet count drops low enough to be dangerous, you should be aware of bleeding gums or nosebleeds and report them to your doctor. They could be signs that your platelet count is too low. If your doctor tells you that your platelet count is low, take these actions to avoid causing injuries that could lead to uncontrolled bleeding.

  • Protect your skin from cuts, scrapes, and sharp objects.

  • Shave with an electric razor.

  • Use a soft toothbrush to prevent bleeding gums.

  • Take steps to prevent constipation, which can lead to hemorrhoids.

  • Call your doctor if you develop a rash, bleeding, or bruising.


Either radiation or chemotherapy can cause diarrhea. When you are having both treatments at once, the problem can be especially severe. The biggest danger when you have diarrhea is dehydration. It’s important to drink plenty of water to replace the fluids your body loses. You can also use these tips to help control your diarrhea.

  • Ask your doctor about medications that may help and take any medications as prescribed. Don’t take over-the-counter medicines without first asking your doctor.

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