Hormone therapy
Different hormone therapy drugs cause different side effects.
This page tells you about some of the side effects that hormone therapy may cause. Your healthcare team will tell you about specific side effects of your own treatment.
It’s important to remember that you probably won't get every side effect listed, everyone is different.
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You may feel more tired when you are taking hormone therapy.
Hormone therapy lowers the amount of testosterone in the body and this might affect:
your ability to get and maintain an erection (erectile dysfunction)
your interest in having sex (libido)
This may get better within 3 to 12 months after the treatment ends.
For some men, erection problems are permanent. It depends on what drug you are having and how long you have been taking it.
Your healthcare team will be able to offer you advice.
Hot flushes and sweating can be troublesome. How often you have them and how long they last will vary from person to person.
Lowered testosterone levels cause hot flushes. They are most likely to happen when taking LHRH agonists ( , because these drugs stop testosterone production altogether.
Getting overheated, drinking tea or coffee, and smoking can all make flushes worse.
They may gradually get better as you get used to the treatment. But, in some men the flushes keep on happening as long as you take the drug.
Talk to your doctor or clinical nurse specialist if you have problems coping with hot flushes and sweating. There are treatments that may help.
Hormone therapy changes the balance of hormones in your body. This can cause breast tissue to grow. This is called gynaecomastia.
Swelling can happen in either one or both breasts. It may be painful. It starts as fatty tissue. But it can develop into thicker (dense) tissue.
You might have a hormone therapy called tamoxifen to help with this. Or you might have a small dose of radiotherapy before treatment starts.
Find out more about gynaecomastia
Pain caused by a secondary prostate cancer can temporarily worsen when you start hormone treatment. This is called tumour flare.
Your doctor should always prescribe another hormone therapy when you start a luteinising hormone blocker. This other hormone therapy helps to prevent tumour flare from causing bone pain. If the pain carries on, your doctor can prescribe drugs called bisphosphonates to treat it.
You might put on weight. You should be able to control this with diet and exercise. But it is often difficult to keep your weight down when you are having hormone treatment. Ask to see a dietitian for advice about managing your weight.
Some people feel that their memory gets worse when they are having hormone therapy and for a while afterwards. There are ways to make life easier, such as making lists so you don't forget things.
Talk to your healthcare team if you feel memory problems are having a significant effect on your life.
Get more information about hormone therapy and memory problems
Some people have mood changes or feel depressed while having hormone therapy. Talking with someone close to you may help. If you don't feel comfortable sharing your feelings with people you know, seeing a counsellor may help.
Men taking hormone therapy for prostate cancer are at risk of bone thinning (osteoporosis). How much bone thinning you might have varies from person to person. Not all hormone treatments cause bone loss.
Your doctor may suggest taking vitamin D and calcium to help lower your risk of problems from osteoporosis.
It might help to:
stop smoking
only drink alcohol within recommended limits
take regular weight bearing exercise, such as walking
Find out more about bone thinning and hormone therapy
Hormone therapy for prostate cancer might increase the risk of heart problems and diabetes. This may partly be because lower testosterone levels can increase the amount of fats (cholesterol) and sugar (glucose) in your blood.
Read more about hormone therapy, heart disease and diabetes
Last reviewed: 06 Feb 2024
Next review due: 05 Feb 2027
Some cancers use hormones to grow or develop. Hormone therapy works by blocking or lowering the amount of these hormones.
Hormone therapy for prostate cancer can affect the levels of your hormones. This can cause different side effects including hot flushes, swollen breasts, sleep disturbances and weight changes.
There are many cancer drugs, cancer drug combinations and they have individual side effects.
Search for the cancer type you want to find out about. Each section has detailed information about symptoms, diagnosis, treatment, research and coping with cancer.
Hormone therapy blocks or lowers the amount of hormones in the body to stop or slow down the growth of cancer.
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