Goserelin implants are injected under the surface of the skin on your stomach.
Each time you collect a prescription, check to make sure it looks the same as you have had before. There are two strengths of implant - Zoladex® 3.6 mg and Zoladex® LA 10.8 mg (long-acting). .
The most common side-effects are hot flushes, sweating, and reduced interest in sex.
|Type of medicine
|A gonadorelin analogue (also known as an LHRH analogue)
|In women: endometriosis; uterine fibroids; breast cancer; to thin the lining of the womb (uterus) before an operation; as part of a treatment for infertility
In men: prostate cancer
|Zoladex®; Zoladex® LA
|Implant and long-acting implant
Goserelin works by acting on the pituitary gland in your brain to stop the production of some of the sex hormones which your body makes naturally. It is given for a number of different conditions. It is used to treat some cancers - prostate cancer in men, and breast cancer in women. It is also given to women for some problems associated with the womb, and to help treat infertility.
Although it is unclear exactly why prostate cancer or breast cancer develops, it is known that the sex hormones testosterone (in men) and oestrogen (in women) increase the growth of these cancers. Goserelin reduces the amount of these hormones, and this helps to stop the growth of the cancer cells.
In women, because it inhibits the production of female sex hormones, it is helpful in treating problems such as endometriosis and uterine fibroids. It is also given to prepare the womb before some surgical operations. Goserelin also encourages ovulation in women, and it is for this reason it is used in infertility treatments.
Goserelin is contained in a small pellet which is implanted (like an injection) under the surface of the skin on your stomach.
Before you have goserelin
Some medicines are not suitable for people with certain conditions, and sometimes a medicine may only be used if extra care is taken. For these reasons, before you are given goserelin it is important that your doctor knows:
- If you have low moods or are depressed.
- If you have high blood pressure.
- If you have been told you have an irregular heartbeat.
- If you have high blood sugar levels (diabetes mellitus).
- If you have any vaginal bleeding for which you do not know the cause (that is, not your normal monthly period).
- If you are taking or using any other medicines. This includes any medicines you are taking which are available to buy without a prescription, as well as herbal and complementary medicines.
- If you have ever had an allergic reaction to a medicine.
How goserelin is given
- Before you are given the implant, ask to read the printed information leaflet from the pack. The manufacturer's leaflet will give you information about the implant and will provide a full list of the side-effects which you may experience from it. If, as a result of reading the leaflet, you have any questions, please discuss them with your doctor/nurse before you have the implant.
- The implant will be inserted for you by a person who has been specially trained. A very small pellet will be inserted just underneath the skin on your stomach.
- Depending on the reason for your treatment, you may require further implants at 4-weekly or 12-weekly intervals. Remember to book your next appointment in plenty of time so that you receive the implant when it is due.
- Try to keep your regular appointments with your doctor so that your progress can be monitored. If your doctor gives you a prescription so that you can collect the goserelin implant from the pharmacy, remember to take it with you for your appointment.
Getting the most from your treatment
- Goserelin can affect your blood sugar levels. If you have diabetes you may need to check your blood glucose more frequently. Your doctor will advise you about this.
- Information for women: if you require contraception while you are on goserelin, use a barrier method such as a condom or cap (diaphragm). Do not use oral contraceptives ('the pill'). If you are using goserelin as a fertilisation treatment, you will already have had a test to show that you are not pregnant. You should not receive goserelin if you are pregnant, or think you might be pregnant.
- Information for men: you may notice that your symptoms become worse when you first start treatment with goserelin and your doctor will give you some tablets to take during the first few weeks to help reduce this. Your symptoms should start to improve after a couple of weeks.
Can goserelin implants cause problems?
Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. The table below contains some of the most common ones associated with goserelin. You will find a full list in the manufacturer's information leaflet supplied with your medicine. The unwanted effects often improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any of the following continue or become troublesome.
|Very common goserelin side-effects (these affect more than 1 in 10 people)
|What can I do if I experience this?
|Hot flushes, sweating (these may continue after stopping treatment with goserelin)
|Take care not to become over-heated
|Erectile dysfunction, reduced interest in sex
|Speak with your doctor for advice
|Headache (in women)
|Drink plenty of water and ask your pharmacist to recommend a suitable painkiller. If the headaches continue, let your doctor know
|Common goserelin side-effects (these affect fewer than 1 in 10 people)
|What can I do if I experience this?
|Vaginal dryness or bleeding, acne (women), changes in breast size, depressed mood, tingling in the fingers or toes, skin rash, bone pain, reactions at the site of injection, decreased bone density, changes in blood pressure, weight changes, and an increased risk of heart attack (men)
|If you are concerned about any of these, speak with your doctor
Important: if you develop a skin rash or have any difficulties with your breathing, you should contact your doctor for advice straightaway. These are rare but possibly serious symptoms, as they may be signs of an allergic reaction.
If you notice any other problems which you think may be caused by the implant, speak with your pharmacist or doctor for advice.
How to store goserelin
- Keep all medicines out of the reach and sight of children.
- Store in a cool, dry place, away from direct heat and light.
Important information about all medicines
If you buy any medicines, check with a pharmacist that they are suitable to take with your other medicines.
If you are having an operation or dental treatment, tell the person carrying out the treatment which medicines you are taking.
Do not keep out-of-date or unwanted medicines. Take them to your local pharmacy which will dispose of them for you.
If you have any questions about your medicines, ask your pharmacist.
Further reading and references
Manufacturer’s PIL, Zoladex® 3.6 mg Implant; AstraZeneca UK Limited, The electronic Medicines Compendium. Dated March 2015.
Manufacturer’s PIL, Zoladex® LA 10.8 mg; AstraZeneca UK Limited, The electronic Medicines Compendium. Dated October 2022.
Medicines Complete BNF 86th Edition; British Medical Association and Royal Pharmaceutical Society of Great Britain, London.