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Medically reviewed by: Ramamoorthy Nagasubramanian, MD

What Is Chemotherapy?

Chemotherapy (often called "chemo") is treatment with medicines that stop the growth of cancer cells.

How Does Chemotherapy Work?

Chemotherapy (pronounced: kee-mo-THER-uh-pee) works by killing cells that are dividing. Most cancer cells divide quickly so they are more likely to be killed by chemotherapy. 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, referred to as an IV. 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, an IV 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 person might have, how long they'll last, and when they'll end. They're different for each person, depending on the type of chemo drug used, the dose, and a person'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 you have side effects, talk with your doctor. Many common side effects of chemo can be treated or managed.

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

    How Can I Take Care of Myself?

    Besides dealing with the many emotions you might feel, you have to manage the physical stuff too. Try these tips for staying comfortable and healthy during cancer treatment:

    • Sleep long, sleep often. Your body needs plenty of rest to recover from chemotherapy. Scale back on strenuous stuff, and make time to get a good night's sleep every night.
    • Focus on good nutrition. If you have nausea, vomiting, and diarrhea, your appetite's probably in the toilet too. Try to stick to foods high in nutrients and eat a balanced diet to prevent weight loss and stay healthy. Several small meals may be easier to eat than fewer larger ones, and eating every few hours can prevent you from feeling too hungry.
    • Ask your doc about anti-nausea medicine. If you feel sick to your stomach a lot, medicines can help relieve nausea.
    • Drink up. You may not feel like drinking, but water, clear broth, juices, and sports drinks can replace fluids lost through vomiting and diarrhea. Room-temperature beverages may be easier to drink than hot or cold liquids.
    • Protect your scalp. To protect your head from sun exposure and irritation, wear soft hats and scarves. Until your hair grows back, you may feel more comfortable wearing hats, scarves, or wigs to school or other events. Or, you may look great without them! Use only mild shampoos and hair products. And talk with your doctor about sunscreen if you're going to be outside.
    • Practice infection protection. Wash your hands well and often, especially before eating, after using the bathroom, and after touching animals. If friends or family members have infections such as colds, the flu, or chickenpox, they should skip visiting until they're feeling better. It's also a good idea to avoid crowds.

    When you're done with chemo, it's still important to see the doctor for follow-up visits. The doctor will ask how you're feeling and whether you're havng any side effects. He or she will also check to see if there are any signs of the cancer coming back.

    Looking Ahead

    If you're one of the many people whose cancer is being treated with chemotherapy, your doctors, nurses, and other members of the cancer treatment team are there to help you and to answer questions before, during, and after chemotherapy.

    Talk with your doctors, nurses, family, and friends if you have any questions or worries. Going through treatment for cancer can be tough, but you are not alone!

    Medically reviewed by: Ramamoorthy Nagasubramanian, MD
    Date reviewed: November 2018