Radiotherapy for prostate cancer may cause side effects, which can occur during treatment, shortly after, or even much later. Early side effects (also called acute side effects) usually happen during or soon after treatment. Side effects vary from person to person, so it’s hard to predict exactly when they will start, how severe they will be, or when they will end. If you have any concerns, speak with your healthcare team—they are there to help.
You may experience side effects or symptoms not listed here, as everyone’s treatment is different. Some side effects might also be caused by other parts of your cancer treatment. Research and support for managing side effects of radiotherapy are continually improving.
Joining a support group can help you share experiences, feel less alone, and cope with the physical and emotional effects of treatment. If you need more support or have any side effects, talk to your treatment or clinical team.
- Key Information: Your reproductive organs (listed below) may be in or near the treatment area. Be sure to ask your consultant if this affects you. If it does, it’s important to discuss any plans or thoughts you have about having children as soon as possible. Your consultant can provide advice tailored to your situation. This can be a sensitive topic, and you may not have all the answers yet, but having the conversation early allows you to explore your options and make informed decisions.
- Reproductive organs include: ovaries, uterus, fallopian tubes, cervix, vagina, penis, testes, scrotum, prostate gland, urethra, and vas deferens.
This page looks at early side effects.
How likely am I to get early side effects?
Before treatment you will discuss and sign a consent form with your clinical oncologist or therapeutic radiographer. They will tell you what to expect, and you can ask questions and discuss any concerns you have about side effects.
You can read different radiotherapy consent forms (HERE) based on the specific area being treated. These consent forms are packed with useful information about early and late side effects.(1)
When you consent to treatment, you are saying you understand that you have a chance of getting side effects. Your team will use words like Expected, Common, Less Common and Rare.
This table shows what these words mean.
| Wording on the consent form | % chance of side or late effect | How many patients will get this? |
| Expected | 50 to 100% | Between half and all patients |
| Common | 10 to 50% | Up to half of all patients |
| Less common | Less than 10% | Fewer than one in ten patients |
| Rare | Less than 1% | Fewer than one in 100 patients |
Early side effects (during or soon after treatment)
- Effects on the bowels: As your treatment goes on, you might need to poo more often (frequency) or need to poo urgently. You might also see more mucus in your poo, have more gas and poo can be watery (loose). It is less common to feel discomfort and pain when you go to the toilet, you may notice the presence of blood in your poo. This is due to the inflammation caused by treatment to the rectum.
- Effects on the bladder and urethra: As your treatment goes on, you might notice some changes with how you wee. You might need to go quickly (urgency). You might need to wee more often (frequency), especially at night (nocturia). It might sting or burn when you wee (cystitis), and you may feel like your bladder isn’t emptying completely (retention). Your wee stream might be weaker or slower (flow). Less commonly bleeding may occur that you can see when you wee (haematuria). Rare side effects are not being able to wee at all, needing a catheter, leaking and loss of control (incontinence). If you cannot wee this is a medical emergency – please seek urgent help.
- Sexual changes: Soreness and tenderness caused by treatment can make it difficult to have penetrative sex. Treatment can sometimes affect your ability to have an erection.
- Fertility: After radiotherapy for prostate cancer, you might produce less semen or no semen. It can also damage sperm and reduce your sperm count. Speak to your team as soon as possible about your options.
- Feeling very tired (fatigue): You might feel very tired during and after your treatment. It’s important to get plenty of rest but sometimes you will still feel really tired, even with lots of sleep. Some tiredness can be caused by having cancer and having cancer treatment, and some is caused by travelling to and from hospital every day for treatment.
- Skin reactions: You might notice a change in colour, swelling, itching, or changes in the texture of your skin where you’re treated. People with lighter skin tones might experience colour changes. These changes can be pink, red or darker than the surrounding area. People with brown and black skin tones might have colour changes such as maroon, purple, yellow or grey pigment changes. Or the skin can look darker than the surrounding area. These changes usually improve after treatment, but this can take 4 to 6 weeks in some cases.
- Hair loss: you might lose hair in the area where you are treated. Often, this grows back over time.
- Sickness: Sometimes you might feel sick (nausea) or be sick, but this is not common
How to feel better during or soon after treatment
Here are some ideas you can try.
- Resting: Get lots of sleep and take breaks if you feel tired.
- Bowel and bladder care: If you are asked to do bowel and bladder preparation before treatment, this can help reduce side effects. During treatment, you will get personalized advice on how to do this.
- Managing Bowel Problems: Professional advice on what food and drink you can have can help. Drink plenty to help keep your poo soft and easy to pass. You can take medicine to help with diarrhea and any sickness. Tell your treatment team of any changes.
- Drinking fluids: Drinking plenty of fluids such as water and squash can help with fatigue and tiredness caused by your treatment. It can also help flush out toxins in your body caused by treatment. You can try diluted juice if you don’t like water.
- Skin reactions: Your treatment team can suggest creams to soothe your skin. Sometimes, extra care is needed if the skin breaks down in the treatment area. Wear loose clothing and stay out of the sun. Talk to your team about washing, shaving and caring for your skin in your treatment area. You might have to change your normal routine during treatment and for a short time after, especially if you have a radiation skin reaction.
- Modern radiation therapy: Remember that with modern targeted radiation therapy, severe side effects are less common and usually go away soon after treatment ends.
- Keeping active: Gentle movement can help you feel better, both during and after treatment. Your treatment team can tell you what is safe for you to do.
- Alcohol use: Please follow the NHS guidelines on safe drinking levels and any instructions you get from your team on what is right for you, your diagnosis and your treatment. If in doubt, please ask your team.
- Stop smoking: If you are looking to stop or reduce smoking, there are services available to help you.
- Sexual changes: Talk to your team if you are having issues. They can offer advice.
- Tell your treatment team: Always let your treatment team know if you have any side effects. They are there to help you.
Click here to learn more about late effects.
Further information
Prostate cancer resources and support:
Learn more about side effects and support here:
Pelvic Radiation Disease Association
Maggie’s | Everyone’s home of cancer care
Learn more about radiotherapy consent forms here:
https://www.rcr.ac.uk/our-services/management-service-delivery/national-radiotherapy-consent-forms/
Resources on sex and cancer:
Sex and cancer | Impact on your sex life and relationships | Macmillan Cancer Support
Learn more about LGBTIQ+ support around cancer treatment and sex:
