Radiation therapy is a common treatment for prostate cancer. It uses high-energy radiation to damage and kill cancer cells. Depending on the type and stage of prostate cancer, radiation may be used as the main treatment, after surgery, or to help control cancer that has spread.
While radiation therapy targets cancer cells, it can also affect some nearby healthy cells. This may cause side effects. Common problems can include tiredness, changes in urination, bowel problems, and sexual problems.
Not everyone has the same side effects. Some people may have only mild symptoms, while others may have more noticeable problems. The side effects can depend on the type of radiation, the area treated, the radiation dose, and the person’s overall health.
In this guide, we will explain the common side effects of radiation therapy for prostate cancer, when they may happen, how long they can last, and what patients can do to manage them.
1. Types of Radiation Therapy for Prostate Cancer
Radiation therapy uses high-energy radiation to kill or control prostate cancer cells. Doctors may use different types of radiation depending on the patient’s cancer and treatment plan.
External Beam Radiation Therapy (EBRT)
External beam radiation therapy, or EBRT, uses a machine outside the body to send radiation toward the prostate.
The radiation is carefully aimed at the prostate to treat cancer while limiting the amount that reaches nearby healthy tissues. However, the bladder and rectum are close to the prostate, so they may also be affected. This can lead to urinary or bowel problems.
Brachytherapy
Brachytherapy is a type of internal radiation therapy. In this treatment, doctors place small radioactive seeds or a radiation source inside or near the prostate.
Because the radiation is placed close to the prostate, it can treat the cancer directly. Some men may have urinary, bowel, or sexual side effects after brachytherapy.
The side effects can be different for each person. Your doctor can explain which type of radiation may be best for you and what side effects you may expect.
2. Common Side Effects of Radiation Therapy
Radiation therapy can also affect some healthy cells near the treatment area. This may cause side effects. Not everyone will have the same problems, and some people may have only mild side effects.
Fatigue
Feeling very tired is a common side effect of radiation therapy. You may feel low on energy during treatment or for some time after treatment ends. The level of tiredness can be different for each person.
Urinary Problems
Radiation can irritate the bladder and urinary tract. You may:
- Need to urinate more often
- Feel a burning sensation when urinating
- Have a stronger urge to urinate
- Notice blood in your urine in some cases
These problems often improve after treatment, but some men may have longer-lasting urinary problems.
Bowel Problems
The rectum is close to the prostate, so it may receive some radiation during treatment. This can cause:
- Loose stools or diarrhea
- A sudden need to have a bowel movement
- Rectal discomfort or irritation
- Blood in the stool in some cases
Most bowel problems improve with time, but some men can have long-term symptoms.
Sexual Side Effects
Radiation therapy can affect sexual function. Some men may have trouble getting or keeping an erection. These problems may develop slowly rather than immediately after treatment.
Radiation can also affect ejaculation and fertility. Your risk may depend on your age, sexual health before treatment, and the type of treatment you receive.
Skin Changes
Some people receiving external radiation may develop skin changes in the treated area. The skin may become irritated or sensitive.
Skin problems depend on the treatment area and the amount of radiation given. Your radiation therapy team can tell you how to care for your skin during treatment.
3. Urinary Side Effects
Radiation therapy can affect the bladder and the tube that carries urine out of the body. This may cause changes in urination.
Some common urinary side effects include:
- Urinating more often: You may feel the need to urinate more often than usual.
- Strong urge to urinate: You may suddenly feel that you need to use the bathroom.
- Burning or discomfort: Some people feel burning or pain when passing urine.
- Trouble starting urination: It may take longer to start the urine flow.
- Weak urine stream: Your urine may come out more slowly or with less force.
- Blood in the urine: A small amount of blood can occur in some people.
These symptoms may improve after treatment. However, tell your doctor if they are severe, getting worse, or making it difficult to pass urine. If you cannot urinate, seek medical help promptly.
4. Bowel and Digestive Side Effects
The rectum is located close to the prostate. Because of this, radiation can sometimes affect the bowel and rectum.
Possible bowel side effects include:
- Diarrhea
- Loose stools
- A sudden need to have a bowel movement
- Rectal irritation or discomfort
- Gas or bloating
- Rectal bleeding in some cases
These problems may start during treatment or after treatment. Many bowel changes improve over time, but some people may have symptoms that last longer.
Tell your healthcare team about ongoing diarrhea, bleeding, pain, or other bowel changes. They may suggest medicines, diet changes, or other ways to manage the symptoms.
5. Sexual Side Effects
Radiation therapy can also affect sexual health. These changes may not happen right away and can sometimes develop months or years after treatment.
Possible sexual side effects include:
Erectile Dysfunction
Some men may have difficulty getting or keeping an erection. The risk can depend on factors such as age, sexual function before treatment, and other treatments received.
Lower Sexual Desire
Some men may notice a lower interest in sex. This can be related to the cancer treatment, tiredness, stress, or hormone therapy if it is given along with radiation.
Changes in Ejaculation
Radiation therapy may change how ejaculation feels or reduce the amount of semen produced. Some men may also have discomfort during ejaculation.
Fertility
Radiation can affect sperm production and fertility. If you may want children in the future, talk with your doctor before treatment about fertility preservation options.
6. Fatigue and General Effects
Fatigue means feeling very tired or having less energy than usual. It is a common side effect of cancer treatment.
Radiation therapy can make you feel tired because your body is using energy to recover from treatment. Other factors, such as stress, poor sleep, pain, or other cancer treatments, can also add to tiredness.
Fatigue may become more noticeable as treatment continues. Some people continue to feel tired for a while after treatment ends.
Simple Ways to Manage Fatigue
- Get enough sleep and rest when you need it.
- Try light physical activity, such as walking, if your doctor says it is safe.
- Eat regular, healthy meals.
- Drink enough fluids.
- Plan important activities for the time of day when you have the most energy.
- Tell your healthcare team if tiredness is severe or affects your daily life.
7. Short-Term vs. Long-Term Side Effects
Radiation therapy side effects can be short-term or long-term.
Short-Term Side Effects
Short-term side effects usually happen during treatment or soon after it. These may include:
- Frequent urination
- Urinary burning or discomfort
- Bowel changes
- Rectal irritation
- Tiredness
Many of these symptoms improve after treatment ends.
Long-Term Side Effects
Some side effects can appear months or even years after radiation therapy. These may include ongoing urinary or bowel problems and changes in sexual function.
However, not every patient develops long-term side effects. The risk can depend on the type of radiation, treatment dose, other treatments, and the person’s overall health.
If you notice a new symptom after treatment, do not assume it is a normal part of recovery. Talk with your doctor or cancer care team so they can find the cause and suggest the right treatment.
8. Factors That Affect Radiation Therapy Side Effects
Not every person has the same side effects from prostate cancer radiation therapy. Several factors can affect how a person feels during and after treatment.
Type and Dose of Radiation
The type of radiation treatment and the amount of radiation used can affect the risk of side effects. External beam radiation therapy and brachytherapy may cause different side effects.
Treatment Area
Radiation is aimed at the prostate, but nearby organs, such as the bladder and rectum, may also receive some radiation. This can lead to urinary or bowel changes.
Overall Health
Your general health can affect how your body handles treatment. Other health problems and medicines may also play a role.
Existing Urinary or Bowel Problems
If you already have urinary or bowel problems before radiation therapy, you may have a higher chance of experiencing related symptoms during treatment.
Other Cancer Treatments
Radiation may sometimes be used with hormone therapy or other treatments. These treatments can cause their own side effects and may change how you feel during treatment.
Your radiation oncology team can explain your personal risk based on your treatment plan and health history.
9. How to Manage Radiation Therapy Side Effects
Many side effects can be managed with simple steps and medical treatment when needed. Always follow the advice given by your healthcare team.
Stay Hydrated
Drink enough fluids unless your doctor has told you to limit them. Good hydration can help support your body during treatment.
Eat Well
Try to eat regular, balanced meals. If bowel problems occur, your healthcare team may recommend certain foods or temporary diet changes.
Stay Physically Active
Light activity, such as walking, may help with tiredness and overall well-being. Do not push yourself, and ask your doctor what level of activity is safe for you.
Ask About Pelvic-Floor Exercises
Pelvic-floor exercises may help some people with urinary control. However, they are not right for everyone or every problem. Ask your healthcare team or a pelvic-floor specialist if these exercises are suitable for you.
Tell Your Oncology Team About Symptoms
Do not wait until a side effect becomes severe. Tell your doctor or nurse about new or worsening symptoms. Early treatment may help prevent a problem from becoming worse.
Medicines and Other Treatments
Your doctor may recommend medicines or other treatments to control specific side effects. Do not start, stop, or change medicines without speaking with your healthcare team.
10. When to Contact Your Doctor
Some side effects are expected during radiation therapy, but certain symptoms need medical attention.
Contact your healthcare team if you have:
- Severe or worsening urinary problems
- Significant or ongoing bleeding
- Persistent or severe diarrhea
- Severe or increasing pain
- Fever or other signs of infection
- New symptoms that concern you
If You Cannot Urinate
Inability to urinate can require urgent medical care. If you suddenly cannot pass urine, seek medical help promptly rather than waiting for the problem to go away.
Remember, you do not have to manage radiation therapy side effects alone. Your cancer care team can help you understand your symptoms and choose the safest way to manage them.
11. Radiation Therapy Side Effects: What Patients Can Expect
Radiation therapy can cause side effects, but not everyone will have the same experience. Some people may have mild symptoms, while others may have more noticeable problems.
The good news is that many side effects can be managed with the right care. Your doctor may suggest medicines, diet changes, exercises, or other treatments based on your symptoms.
Your treatment plan is made for you. The type of radiation, dose, treatment area, overall health, and other treatments can all affect your risk of side effects.
If you are worried about a side effect, talk to your healthcare team. Do not stop or change your cancer treatment on your own. Your doctor can help you understand the benefits and risks and decide what is best for you.
12. Frequently Asked Questions About Radiation Therapy Side Effects
How long do radiation side effects last?
It depends on the side effect and the person. Some symptoms start during treatment and improve after treatment ends. Other side effects may take longer to improve.
Does radiation therapy cause erectile dysfunction?
It can. Some men may develop problems getting or keeping an erection after prostate radiation therapy. The risk can depend on factors such as age, sexual function before treatment, and other treatments.
Can radiation affect bowel movements?
Yes. Radiation can affect the rectum and bowel because they are close to the prostate. Some people may experience diarrhea, loose stools, bowel urgency, gas, or rectal irritation.
Does prostate radiation cause urinary problems?
Yes. Some men may have frequent urination, a strong urge to urinate, burning, difficulty starting urine flow, or a weaker urine stream. These symptoms often improve after treatment, but some may last longer.
Are radiation side effects permanent?
Not always. Many side effects improve with time. However, some urinary, bowel, or sexual problems can last for a long time or develop later. Your doctor can explain the risks based on your treatment.
Can side effects appear years after treatment?
Yes. Some late side effects can develop months or years after radiation therapy. This does not mean that everyone will experience them.
How can radiation side effects be managed?
Treatment depends on the side effect. Your healthcare team may recommend medicines, diet changes, physical activity, pelvic-floor exercises when appropriate, or other treatments. Tell your doctor about any new or worsening symptoms.
13. Conclusion
Radiation therapy is an important treatment option for many people with prostate cancer. Like other cancer treatments, it can cause side effects such as urinary problems, bowel changes, fatigue, and sexual problems.
The type and severity of side effects can be different for every person. Some symptoms may improve after treatment, while others may last longer or appear later.
If you are receiving radiation therapy for prostate cancer, talk openly with your radiation oncologist and healthcare team about any symptoms or concerns. Do not stop your treatment without discussing it with your doctor. Your healthcare team can help you understand what to expect and find ways to manage side effects safely.