[Skip to Content]

What Is Chemotherapy?

Chemotherapy (often called "chemo") is treatment with medicines that kill or stop the growth of cancer cells. Standard chemotherapy drugs are different from a class of drugs called targeted therapy. Targeted therapy drugs can precisely target the cancer cells while causing less damage to normal cells and tissues.

How Does Chemotherapy Work?

Chemotherapy works by killing cells that are dividing. Most cancer cells divide quickly, so they're more likely to be killed by chemotherapy. But some normal cells that divide quickly can also be destroyed.

Chemo is different from radiation therapy, which can destroy cancer cells in a specific area of the body. Chemotherapy works to treat cancer cells that may have spread throughout the body.

How Is Chemotherapy Given?

There are several ways to give chemotherapy.

  • In most cases, a person gets chemo intravenously (into an IV line). An IV is a tiny tube put into a vein through the skin, usually in the arm. The tube is attached to a bag that holds the medicine. The chemo medicine flows from the bag into the vein, putting the medicine into the bloodstream. Then the medicine travels through the body to attack cancer cells.

    Sometimes, a larger, permanent IV (called a central line) is put into a larger blood vessel under the skin of the upper chest. That way, a person can get chemotherapy and other medicines through the IV and doctors won't always use a vein in the arm.

Chemo also can be:

  • taken as a pill, capsule, or liquid that is swallowed
  • given by injection into a muscle or the skin
  • injected into spinal fluid through a needle put into a fluid-filled space in the lower spine (below the spinal cord)

What Side Effects Can Happen From Chemotherapy?

Chemo damages or kills cancer cells. But it also can damage normal, healthy cells. This can lead to side effects.

It's hard to know which side effects a child might have, how long they'll last, and when they'll end. They're different for each child, depending on the type of chemo drug used, the dose, and a child's general health.

The good news is that most side effects are temporary. As the body's normal cells recover, the side effects start to go away. If your child has side effects, talk with your doctor. Many common side effects of chemo can be treated or managed.

After chemo, the doctor will check your child's health during follow-up checkups. The doctor will ask if your child still has any side effects and will watch for any signs that the cancer is coming back.

How Can I Help My Child?

Your child may have many questions about cancer and its treatment. Be honest when talking about it. Use age-appropriate language and encourage your child to share their feelings.

Kids who are worried about starting chemo might benefit from a tour of the hospital or clinic before treatment begins. Also look for support groups for families coping with childhood cancer. Meeting other cancer patients and survivors might help your family develop a network of friends and supporters dealing with the same issues.

Accept help from family and friends, both early in your child's treatment and later on. Taking care of yourself will help you better care for your child.

What Else Should I Know?

Learning that a child has cancer is upsetting, and cancer treatment can be stressful for any family. While it can be a long road, children and teens treated for cancer often go on to lead long, healthy, and happy lives.

And you're not alone. Doctors, nurses, counselors, social workers, Child Life therapists, and other members of the care team are there to answer questions and support you and your child before, during, and after chemotherapy.

You also can find information and support online at:

Medically reviewed by: Andrew W. Walter, MD
Date reviewed: September 2024