The side effects you experience will vary depending on the type and dose of radiation, and the areas treated. You may experience some of the following side effects. Most side effects are temporary and tend to improve gradually in the weeks after treatment ends, though some may continue for longer. Some side effects may not show up until many months or years after treatment. These are known as late effects. Talk to your doctor or treatment team about ways to manage any side effects you have.
Learn more about:
Short-term side effects
| fatigue | The effects of radiation on your body may mean you become tired during treatment. Fatigue may build up during treatment and usually improves 1–2 months after treatment ends, but occasionally can last up to three months. |
| urinary problems | Radiation therapy can irritate the lining of the bladder and the urethra. This is known as radiation cystitis. You may pass urine more often or with more urgency, have a burning feeling when urinating or a slower flow of urine. If you had urinary issues before treatment, you may be more likely to have issues with urine flow. Blood may appear in the urine, which may require further treatment. If you are unable to empty your bladder (urinate) right after brachytherapy, you may need a temporary catheter for a few days or weeks. |
| bowel changes | Radiation therapy can irritate the lining of the bowel and rectum. Symptoms may include passing smaller, more frequent bowel motions, needing to get to the toilet more quickly, or feeling that you can’t completely empty the bowel. Less commonly, there may be some blood in the faeces (poo or stools). If this happens, let your doctor know as there are treatments that can stop the bleeding. |
| ejaculation changes | You may notice that you feel the sensation of orgasm but ejaculate less or no semen after radiation therapy. This is known as dry orgasm, which may be a permanent side effect. In some rare cases, you may experience pain when ejaculating. The pain usually eases over a few months. |
Long-term or late effects
| infertility | Radiation therapy to the prostate usually causes infertility. If you might want to have children, speak to your doctor before treatment about sperm banking or other options. |
| urinary problems | Bladder changes, such as frequent or painful urination, can also be late effects, appearing months or years after treatment. After brachytherapy, scarring can occur around the urethra, which can block the flow of urine and require corrective procedures. It is important to let your doctor know if you have any problems with urinating or bleeding. |
| bowel changes | Bowel changes, such as diarrhoea, wind or constipation, can also be late effects, appearing months or years after treatment. Bleeding from the rectum can also occur. In rare cases, there may be loss of bowel control (faecal incontinence) or blockage of the bowel. It is important to let your doctor know about any bleeding or if you have pain in the abdomen and difficulty opening your bowels. |
| erection problems | The nerves and blood vessels that control erections may become damaged. This can make it difficult to get and keep an erection, especially if you’ve had these problems before treatment. Having androgen deprivation therapy (ADT) can also contribute to problems with erections. Erection problems may take a while to appear and can be ongoing. |
→ READ MORE: Androgen deprivation therapy (ADT)
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A/Prof Ian Vela, Urologic Oncologist, Princess Alexandra Hospital, Queensland University of Technology, and Urocology, QLD; A/Prof Arun Azad, Medical Oncologist, Urological Cancers, Peter MacCallum Cancer Centre, VIC; A/Prof Nicholas Brook, Consultant Urological Surgeon, Royal Adelaide Hospital and A/Prof Surgery, The University of Adelaide, SA; Peter Greaves, Consumer; Graham Henry, Consumer; Clin Prof Nat Lenzo, Nuclear Physician and Specialist in Internal Medicine, Group Clinical Director, GenesisCare Theranostics, and Notre Dame University Australia, WA; Henry McGregor, Men’s Health Physiotherapist, Adelaide Men’s Health Physio, SA; Jessica Medd, Senior Clinical Psychologist, Department of Urology, Concord Repatriation General Hospital, NSW; Dr Tom Shakespeare, Director, Radiation Oncology, Coffs Harbour, Port Macquarie and Lismore Public Hospitals, NSW; A/Prof David Smith, Senior Research Fellow, Daffodil Centre, Cancer Council NSW; Allison Turner, Prostate Cancer Specialist Nurse (PCFA), Canberra Region Cancer Centre, Canberra Hospital, ACT; Maria Veale, 13 11 20 Consultant, Cancer Council QLD; Michael Walkden, Consumer; Prof Scott Williams, Radiation Oncology Lead, Urology Tumour Stream, Peter MacCallum Cancer Centre, and Professor of Oncology, Sir Peter MacCallum Department of Oncology, The University of Melbourne, VIC
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