Preventing Infections in People With Cancer

Infection is one of the most common life-threatening complications of cancer and cancer treatment. This is because cancer and cancer treatment weaken the immune system. The immune system is a complex system by which the body resists infection by germs, such as bacteria or viruses.

This is one part of a series on information about cancer patients and their risk of infection.

Things people with cancer can do to help prevent infections

Here are some things you can do that might help prevent infection and illness when your immune system is weak due to cancer and/or cancer treatment:

  • Wash your hands often with soap and warm water. Be sure to wash your hands before eating and before touching your face or mucous membranes (eyes, nose, mouth, etc.).
  • Wash your hands after using the bathroom, blowing your nose, coughing, or sneezing.
  • Wash your hands after touching animals, collecting trash, or taking out garbage.
  • Wash your hands after visiting a public place or touching items used by others.
  • Carry an alcohol-based hand sanitizer to clean your hands when you’re out.
  • Use moist cleaning wipes to clean surfaces and things that you touch, such as door handles, ATM or credit card keypads, and any items that are used by other people.
  • Avoid large crowds of people such as school, travel, shopping, social events, and public gatherings.
  • Stay away from anyone with a fever, the flu, or other infection.
  • Get your flu shot every fall. Encourage other members of your household to get it, too. DO NOT get the nasal mist flu vaccine.
  • Bathe every day. Be sure to wash your feet, groin, armpits, and other moist, sweaty areas.
  • After bathing, look for redness, swelling, and/or soreness where any tubes or catheters go into your body.
  • Wear gloves when you garden and wash up afterward.
  • Brush your teeth twice each day. Ask your doctor or nurse if it’s OK to gently floss your teeth. Tell them if your gums bleed. Your doctor or nurse may give you a special mouthwash to help clean your mouth. Do not use alcohol-based mouthwash.
  • Keep your groin and anal areas clean. Use soft moist tissues such as disposable baby wipes or bathroom towelettes after using the toilet and anytime you notice irritation or itching. Tell your doctor about any bleeding, redness, or swelling (lumps) in this area.
  • Do not get manicures or pedicures at salons or spas (you can use your own personal and well-cleaned tools at home). Do not use false nails or nail tips.
  • Do not wade, play, or swim in ponds, lakes, rivers, or water parks.
  • Do not get into hot tubs.
  • Wear shoes all the time – in the hospital, outdoors, and at home. This helps you avoid injury and keep germs off your feet.
  • Use an electric shaver instead of a razor to avoid cuts and nicks. Do not share shavers.
  • If you cut or scrape your skin, clean the area right away with soap and warm water. Cover the area with a clean bandage to protect it. If the bandage gets wet or dirty, clean the area and put on a new bandage. Tell your doctor if you notice redness, swelling, pain, or tenderness.
  • Prevent constipation and straining to move your bowels (poop) by drinking 2 quarts of fluid each day. Exercising each day can help, too. Let your doctor or nurse know if you are having bowel problems. If needed, your doctor may give you medicine that softens your poop. Do not put anything in your rectum, including enemas, thermometers, and suppositories.
  • Women should not use tampons, vaginal suppositories, or douche.
  • Use water-based lubricants during sex to avoid injury or abrasion of the skin and mucous membranes. Use latex or plastic condoms to reduce the risk of sexually transmitted infections.
  • Do not keep fresh flowers or live plants in your bedroom.
  • Do not clean up droppings from your pets. Do not clean bird cages, litter boxes, or fish or turtle tanks. Have someone else do this for you.
  • Do not touch soil that may contain feces (poop) of animals or people.
  • Do not change diapers, but if you do, wash your hands very well afterward.
  • If you use disposable gloves to avoid touching things like soil or waste, wash your hands after you take off the gloves. (Gloves can have tiny holes that you can’t see.)
  • Stay away from all standing water, for example, in vases, denture cups, and soap dishes. If you store your dentures in a cup, wash the cup and change the water with each use.
  • Use hot water to clean your dishes.
  • Do not share bath towels or drinking glasses with anyone, including family members.
  • Stay away from chicken coops, caves, and any place where dust from the ground is being blown into the air, such as construction sites.
  • Talk with your doctor or nurse if you are planning any travel during this time.

Be aware of and watch for signs and symptoms of infection. Talk to your doctor about what you should watch for and what you need to report right away. (See Infections in People With Cancer to learn more about common signs and symptoms of infection.)

Food safety tips for the person with cancer

Infections can be picked up from food and drinks. So, food safety is very important when your immune system is weak. Talk to your cancer care team about whether you need to follow a special diet during your cancer treatment.

You can learn a lot about how to eat well and protect yourself from food-related infections in Nutrition for the Person With Cancer During Treatment.

About eating fresh fruits and vegetables: Fresh fruits and vegetables can have germs on the outside which can cause illness. Some doctors tell their patients who have weak immune systems not to eat any fresh fruits or vegetables to help lower the risk of infection. Others allow their patients to eat fresh fruits and vegetables as long as they are washed thoroughly first. It’s important to know that even when the outer part of a fruit (such as the peel or rind) isn’t eaten, it still needs to be washed before it’s peeled. If it isn’t, germs can get on the part that is eaten when the peel or rind is cut. It may also be a good idea to avoid certain foods that have been linked to outbreaks before, such as raw vegetable sprouts, fresh salsa, and berries.

Talk with your doctor about any dietary questions or concerns you may have, or ask to talk with a registered dietitian.

Medicines to prevent infections during cancer treatment

Sometimes, doctors prescribe medicines when a person’s immune system is very weak – even though there’s no sign of infection. The drugs are given to help keep you from getting an infection.

Preventive antibiotics

Anti-bacterial, anti-viral, and/or anti-fungal drugs may be used to help prevent infection. You may hear this called prophylactic antibiotic use, or just prophylaxis. Prophylaxis is only used when there’s a very high risk of getting infections (the immune system is very weak). You might also be given antibiotics if you are taking other medicines that can weaken your immune system, such as a long course of steroids or certain chemotherapy drugs.

The prophylactic antibiotics are stopped when your immune system is no longer so weak (often some time after the immune-weakening drugs are stopped). Using antibiotics in this way does not prevent all infections. That means it’s still important to use the same precautions as when you aren’t taking preventive antibiotics, and be sure to tell your doctor about any new signs of infection.

Growth factor drugs

Growth factors are proteins your body makes to help your blood cells grow. They are also known as colony-stimulating factors (CSFs).

You can be given injections of man-made CSFs. They are most often used after chemo to help prevent infection. Your doctor also may give you a CSF if your immune system is weak and you have a serious infection that’s getting worse even though you’re getting treatment.

Common CSF drugs used today include filgrastim (Neupogen®), pegfilgrastim (Neulasta®), and Sargramostim (Leukine®). All of these drugs cause the body to make the blood cells that help fight infection.

Growth factors can have serious side effects in some people, but they can reduce the risk of infection in the patients who need them. Talk to your cancer care team about the risks and benefits of CSFs.

The American Cancer Society medical and editorial content team

Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.

National Cancer Institute. Chemotherapy and You: Support for People with Cancer. Accessed at on January 28, 2015.

National Comprehensive Cancer Network. Prevention and Treatment of Cancer-Related Infections. V.2.2014, 8/11/14 Accessed at on January 28, 2015.

Last Medical Review: February 25, 2015 Last Revised: February 25, 2015

American Cancer Society medical information is copyrighted material. For reprint requests, please see our Content Usage Policy.