Cancer Health Center

What to Expect From Radiation Therapy

Radiation therapy treats cancer by using high-energy waves to kill tumor cells. The goal is to destroy or damage the cancer without hurting too many healthy cells.

This treatment can cause side effects, but they’re different for everyone. The ones you have depend on the type of radiation you get, how much you get, the part of your body that gets treatment, and how healthy you are overall.

There’s no way to predict how radiation will affect you. You may have few or only mild side effects from your treatment; someone else may have a lot of problems or very severe ones.

When you get radiation therapy, you’ll work with a doctor who specializes in this type of medicine. It's important to talk with her about how the treatment might make you feel and what you can do to feel better. If the therapy makes you uncomfortable, speak up. If you keep your health team informed, they can help you get through treatment.

How Soon Might I Have Side Effects From Radiation Therapy?

There are two kinds of radiation side effects: early and late. Early side effects, such as nausea and fatigue, usually don’t last long. They may start during or right after treatment and last for several weeks after it ends, but then they get better. Late side effects, such as lung or heart problems, may take years to show up and are often permanent when they do.

The most common early side effects are fatigue and skin problems. You might get others, such as hair loss and nausea, depending on where you get radiation.

How Can I Handle Fatigue?

The fatigue you feel from cancer and radiation therapy is different from other times you may have felt tired. It’s an exhaustion that doesn’t get better with rest and can keep you from doing the things you normally do, like going to work or spending time with family and friends. It also can seem different from day to day, which makes it hard to plan around it. It can even change how well you're able to follow your cancer treatment plan.