Skip to main content

Health library

Back to health library

Chemotherapy: How to protect yourself from infection

If you're receiving chemotherapy, it's vital that you learn how to avoid infections and what to do if one occurs.

Chemotherapy can be an effective and even lifesaving treatment for cancer. But like many powerful medicines, its benefits come with the potential for side effects.

Common side effects of chemotherapy include fatigue, nausea, anemia, a loss of appetite and hair loss, according to the National Cancer Institute (NCI).

The most dangerous, however, may be an increased risk for infection.

For people with cancer, any infection is an emergency, according to the Centers for Disease Control and Prevention (CDC). A cut on the finger that becomes inflamed isn't just an annoyance; it's a serious concern that can spur a trip to the hospital.

That's why it's vital for those on chemotherapy to know how to protect themselves from infection and what to do if it occurs.

Why chemo raises infection risk

Cancer grows through uncontrolled replication of its malignant cells. Chemo drugs target these cancer cells, destroying them and attempting to stop new ones from growing.

But the drugs also can affect production of healthy cells, such as white blood cells (WBCs), which are manufactured by bone marrow to help fight infection. A WBC of particular importance is called a neutrophil. When you have too few of those, you have neutropenia—and a compromised immune system that is weakened against infection.

How to protect yourself

The first rule for avoiding infection is the same for everyone, whether you're undergoing chemotherapy or not: Wash your hands well and often.

Below are additional protective steps you can take, from the American Cancer Society (ACS), NCI and others.

Avoid germs. Stay away from crowds and from ill individuals, even if all they have is a cold. Avoid people who have recently been immunized with a live virus vaccine for polio or chickenpox. Don't get any shots yourself without checking with your doctor first. Carry a pack of sanitizing wipes so you can clean doorknobs, ATMs or anything else that you need to touch.

Also, don't be shy about asking anyone who comes near you to wash their hands.

Prevent cuts and injury. Be very careful with knives, scissors and other sharp tools. Use an electric shaver instead of a razor.

Clean yourself gently. Bathe with warm, not hot, water. Afterward, pat yourself dry—don't rub. To avoid irritation, use baby wipes or a spray bottle to clean yourself after a bowel movement.

Pay attention to oral hygiene. If you can, visit your dentist at least two weeks before starting chemotherapy. (Once you've started chemo, you'll need to check with your doctor before making a dental appointment.) Brush your teeth after every meal and before bedtime—using an extra-soft toothbrush. And use an alcohol-free mouthwash.

Be strict about food safety. Don't eat raw or undercooked meat, seafood, chicken or eggs. Wash your hands well throughout food preparation and especially after handling raw meat. Wash raw fruits and vegetables. Find more detailed guidelines at the government's food safety website, foodsafety.gov.

Ask others to clean up after pets. Don't clean the fish tank or cat box. And hand over dog-poo pickup duty to someone else.

Your blood count will be checked throughout your treatment, so ask your doctor to let you know when your WBCs are low. That's when you're most at risk for infection, so be extra cautious during that time.

If your WBC levels fall too much, your doctor might reduce your chemo dose or give you medication to try to kick your bone marrow's cell production into higher gear.

Red flags: When to call your doctor

The NCI recommends checking your temperature orally at least once a day. Ask your pharmacist to recommend a good digital thermometer.  Many doctors will recommend you call them right away if your temperature rises above 100.5 degrees, but this threshold can vary, so be sure to ask.

You should also call your doctor if you notice:

  • Chills or sweats.
  • Sore throat, cough or stuffy nose.
  • Headache, sinus pain or ear pain.
  • Shortness of breath.
  • Neck pain or stiffness.
  • Burning during urination.
  • Nausea, vomiting or diarrhea.
  • Redness, soreness or swelling anywhere.
  • Sores or white coating in the mouth or on the tongue.

You can assess your risk for infection and find other information at CDC's website preventcancerinfections.org.

Reviewed 6/22/2021

Related stories