Each person's reaction to any medication is different. Many people have very few side effects with Zoladex, while others may experience more. We have outlined the most common side effects. However, we have not included those that are very rare and therefore extremely unlikely to affect you. If you notice any effects that you think may be due to the drug, but which are not listed here, please discuss them with your doctor or nurse.
You will see your doctor regularly while you have this treatment so that they can monitor the effects. This information should help you to discuss any queries about your treatment and its side effects with your doctor or nurse, as they are in the best position to help and advise you.
Some people may have some of the following side effects:
Tumour flare There may be a temporary increase in the levels of testosterone for the first few days of starting Zoladex. Because of this, you may find that you have an increase in symptoms over the first two weeks. You may experience an increase in bone pain or have problems passing urine. Other problems may occasionally occur due to a temporary increase in the size of the tumour. This is known as tumour flare. If you have any problems, you will need to let your doctor know. Other hormonal therapy drugs such as cyproterone acetate, flutamide or bicalutamide may be given for the first few weeks of starting Zoladex, to prevent tumour flare from occurring.
Hot flushes These can be quite common. Many men find that the hot flushes wear off after a period of time. There are a number of ways to help to reduce or control hot flushes and sweats. Some people find it is helpful to cut down on tea, coffee, nicotine and alcohol. Recent research suggests that progestogen or some anti-depressants may be helpful in controlling this side effect. Your nurse or doctor can discuss this with you.
Some men find complementary therapies helpful. Your GP may be able to give you details about obtaining these on the NHS.
Loss of sex drive (libido) and erection difficulties (impotence) These effects are rare and (if they occur) will usually return to normal after stopping the drug. Your doctor or nurse can discuss this with you.
Lowering of libido (sex drive) and impotence (loss of ability to have an erection) These effects are rare, but if they do occur sexual function will usually return to normal after stopping the drug. Your doctor or nurse can discuss this with you.
Breast tenderness or fullness You may sometimes notice slight breast swelling and tenderness known as gynaecomastia. Your doctor can prescribe medicines to reduce any discomfort.
Skin rashes Some people experience skin rashes. Let your doctor know if this occurs.
Sore joints Some people may have soreness in their joints, but this is usually mild and will stop when the treatment is finished.
Weight gain and tiredness You may notice that you gain a few pounds in weight and may feel less energetic than usual. This usually subsides when the Zoladex treatment is stopped.