Radiotherapy

Side effects of lung cancer radiotherapy

Side effects vary from person to person. You may not have all of the effects mentioned.

About side effects

Side effects tend to start a week after the radiotherapy begins. They gradually get worse during the treatment and for a couple of weeks after the treatment ends. But they usually begin to improve after around 2 weeks or so.

If you have had stereotactic radiotherapy, you might get side effects during treatment or up to 12 weeks after treatment.

Short term side effects

Side effects can include:

Long term side effects

Most side effects gradually go away in the weeks or months after treatment. But some side effects can continue or might start some months or years later.  

Side effects if you have chemotherapy with radiotherapy

Chemotherapy combined with radiotherapy can make some side effects worse. Combining these treatments is called chemoradiotherapy.

Read more about side effects of chemoradiotherapy

Last reviewed: 10 Oct 2025

Next review due: 10 Oct 2028

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