Side effects tend to start a few days after the radiotherapy begins. They usually begin to improve between 1 and 3 weeks after the end of treatment.
Everyone is different and the side effects vary from person to person. You may not have all of the effects mentioned.
You might feel tired during your treatment. It tends to get worse as the treatment goes on. You might also feel weak and lack energy. Rest when you need to.
Tiredness can carry on for some weeks after the treatment has ended but it usually improves gradually.
Various things can help you to reduce tiredness and cope with it, such as exercise. Some research has shown that taking gentle exercise can give you more energy. It's important to balance exercise with resting.
Radiotherapy can make your skin sore because the skin round the penis is sensitive. This usually happens after 3 to 4 weeks of treatment.
Tell your nurse, doctor or radiographer if your skin starts to break down, or if you have any discharge or an ulcer. If this happens, your skin can get infected.
Rubbing can make the soreness worse. Wash the area only with plain water and simple soaps, such as baby soap. Pat the skin dry with a soft towel and don’t rub it. Avoid perfumed or medicated soaps and creams. Before you use any creams or products, check with your doctor, radiotherapy nurse, or radiographer.
The radiotherapy nurse can give you advice if you're worried. The soreness gets better after your treatment is over.
Your penis might become swollen and inflamed. This swelling can cause pain. Tell your doctor, nurse or radiographer if you have pain so that they can give you painkillers. The swelling goes down when you finish your treatment.
Side effects if you have chemotherapy with radiotherapy (chemoradiotherapy)
Chemotherapy combined with radiotherapy can make some side effects worse. Speak to your doctor or nurse if you are worried about side effects.
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.