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Side effects

Side effects tend to start a few days after the radiotherapy begins. They gradually get worse during the treatment. They can continue to get worse after your treatment ends. But they usually begin to improve after 1 or 2 weeks.

Everyone is different and the side effects vary from person to person. You might not have all of the effects mentioned.

Side effects can include:

Radiotherapy causes tiredness.

Tiredness starts during your course of treatment. It usually lasts for about a week after your treatment has finished and then gradually gets better.

You might also feel weak and lack energy. Staying active can help.

Sometimes the skin in the treatment area gets red and sore – a bit like mild sunburn.

This is not usually too bad with radiotherapy for testicular cancer, particularly if you only need radiotherapy for 2 weeks.

Most men with testicular cancer having radiotherapy have their tummy (abdomen) treated.

This can cause sickness. It's usually mild. You may not have it at all.

If you feel sick, tell your doctor, radiographer or radiotherapy nurse. Your doctor should give you anti sickness tablets to take every day before your treatment.

Tell them if you still have sickness despite the tablets. You can try another type of anti sickness tablet. Some work better for some people than others.

If you don't feel like eating, you could try a high calorie food supplement drink. You can get these at most chemists or your doctor can prescribe them.

If you have problems with your diet, ask to see a dietitian at the hospital.

Most men having radiotherapy for testicular cancer have their tummy (abdomen) treated.

This can cause diarrhoea. It's usually mild. You may not have it at all.

Diarrhoea can be helped with medicine to slow down your bowel.

Eating a low fibre diet may help. Your radiotherapy department may have leaflets to help you with this.

You cut out:

  • whole grain cereals
  • wholemeal bread
  • bran
  • dried fruit
  • cabbage

You cut down on:

  • fruit juice
  • fresh fruit
  • vegetables

You can eat bananas - they may actually help. 

You can go back to your healthy diet after the treatment is over.

If you have frequent diarrhoea, drink plenty of fluids.

During radiotherapy treatment to the lymph nodes in the tummy (abdomen) beams are directed at:

  • an area down the middle of the stomach or abdomen
  • sometimes at the groin

A lead shield protects the testicle from the radiotherapy beams. But there is a small risk that your remaining testicle could get a dose of radiation.

Doctors advise men not to try to father a child when having radiotherapy treatment, and for up to a year afterwards. After this time, the risk of abnormalities in the baby is not increased.

Last reviewed: 
22 Jul 2020
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    J Oldenburg and others
    Annals of Oncology, 2013, 24 (supplement 6 ): vi125-vi132

  • EAU Guidelines on Testicular Cancer

    P Albers and others

    European Association of Urology 2016

  • Cancer and its Management (7th edition)

    J Tobias and D Hochhauser 

    Wiley Blackwell 2015

  • Cancer Priniciples & Practice of Oncology (10th edition)

    V T DeVita Jr, T S Lawrence and S A Rosenberg

    Wolters Kluwer 2015

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