Side Effects of Cancer Treatment

Photo of a woman with cancer sitting by her window holding her granddaughter.

Hair loss is one of the best known side effects of chemotherapy, but neutropenia is one of the most dangerous.

Cancer treatments may have many side effects. A side effect occurs when treatment damages healthy cells. Side effects can be different for each person, and for different medicines and kinds of treatment.

If you think you’re experiencing any side effects, talk to your medical team. They may be able to help you manage themExternal in a variety of ways.


Neutropenia is a decrease in the number of white blood cells, which are the body’s main defense against infection. Neutropenia is common after receiving chemotherapy.

Chemotherapy drugs work by killing fast-growing cells in the body—cancer cells and healthy white blood cells. During chemotherapy, you may have fewer than normal white blood cells to fight germs, so you’re more likely to get an infection.

Washing your hands often will lower your chance of getting an infection during chemotherapy. Talk with your doctor about other ways to lower your risk of getting an infection. You should call your doctor right away if you notice any signs of an infection, especially a fever.


If you have lymph nodes removed during surgery, or if radiation treatment damages a lymph node or vessel, the lymph fluid may not be able to drain properly. The fluid may build up under your skin and cause part of your body to swell. This condition is called lymphedema. Learn more about lymphedema.

Hair Loss

Photo of Traci Ramirez

“Surviving cancer and losing my hair has been a very hard thing for me! When my hair started coming out, I immediately went to my hair salon and had it shaved off. Looking back now, I am able to say hair is only hair. Still, I’m very happy that finally my hair grew back,” says breast cancer survivor Traci.

Some kinds of chemotherapy can make your hair fall out. This condition is called alopecia. Hair usually grows back two to three months after treatment ends.

A cooling capExternal may help you keep more of your hair. A cooling cap fits tightly on your head and keeps your scalp cold before, during, and after your chemotherapy treatment. Studies have found that how well a cooling cap works depends on the kind of chemotherapy you receive. Talk to your doctor about a cooling cap before you start chemotherapy.

Some people choose to shave their head before their hair starts to fall out, or to wear a wig, hat, or scarf during chemotherapy treatment. The American Cancer Society offers tips on coping with hair loss.External

Nausea and Vomiting

Cancer treatments can make you feel sick to your stomach, and to vomit. Sometimes, cancer patients feel sick just from thinking about cancer treatment.

Fortunately, medicines can help control nausea and make you feel better. Tell your doctor when you feel sick, so he or she can find the medicine that works best for you.

Nausea can be managed in other ways as well. Drinks like water or ginger ale may help. Some people use relaxation techniques, hyponosis, or acupuncture. The American Cancer Society has more information.External

Problems with Thinking and Remembering Things

The drugs used to treat cancer can cause some people to have trouble concentrating or remembering things. This is often called “chemo brain,”External and it can make it hard for cancer patients to do their jobs or everyday tasks.

Tips for coping with this problem include getting plenty of sleep, making notes of your daily plans and setting reminders on your smart phone, and focusing on one task instead of trying to do several things at the same time.

Cancer Pain

Pain Control: Support for People with Cancer

Get tips on how to manage cancer pain and talk to your health care team about it in this video.

Cancer itself and treatments for it may cause pain. Pain can make it harder to do your normal activities, and lower your quality of life.

Pain control is an important part of your cancer treatment plan. Talk to your doctor if you have pain. Your doctor will figure out what is causing the pain and the best way to control it. For more information, visit Pain in People with Cancer.External

Other Side Effects

Cancer treatments can cause many other side effects, including tiredness, trouble eating, and depression. The National Cancer InstituteExternal and the American Cancer SocietyExternal describe many of these problems and offer tips for preventing or coping with them.

Page last reviewed: February 5, 2019