Indications
Goserelin is a hormone treatment used for prostate cancer, hormone-sensitive breast cancer in women who have not yet gone through menopause, endometriosis, and uterine fibroids. It is also used to thin the lining of the womb before certain procedures and, in some fertility programmes, to control the hormone cycle before ovarian stimulation.
How It Works
Goserelin is a man-made version of gonadotropin-releasing hormone (GnRH). When given continuously, it first causes a short rise in hormones, then switches off the pituitary gland’s signals to the testes or ovaries. This greatly lowers testosterone in men and oestrogen in women. Many prostate and breast cancers, as well as endometriosis and fibroids, need these hormones to grow, so lowering them slows the disease and relieves symptoms.
Dosage and Administration
Goserelin is given as a small implant injected under the skin of the abdomen by a doctor or nurse, usually every 4 weeks or every 12 weeks depending on the strength used. The dose, schedule and length of treatment are decided by your specialist and given as prescribed. A local anaesthetic may be used before the injection. Try not to miss appointments, as the effect depends on regular dosing.
Interactions
Lowering testosterone can affect heart rhythm, so care is needed with medicines that prolong the QT interval, such as Amiodarone, Sotalol, Quinidine, Methadone, Moxifloxacin, some antipsychotics and Ondansetron at high doses. In prostate cancer, an anti-androgen such as Bicalutamide is often given at the start to block the early hormone surge. Tell your doctor about all medicines you take.
Contraindications
Do not use if you are allergic to Goserelin or similar medicines, are pregnant, or are breastfeeding. It is not used for non-cancer conditions in women with undiagnosed vaginal bleeding.
Side Effects
Common side effects include hot flushes, sweating, reduced sex drive, erectile problems in men, vaginal dryness and breast changes in women, mood changes or low mood, headache, tiredness, weight changes, joint pain and pain or bruising at the injection site. Long-term use can thin the bones. In the first weeks of prostate cancer treatment, bone pain or urinary symptoms may temporarily worsen (tumour flare). Raised blood sugar and changes in blood pressure can occur.
Get urgent medical help for bleeding, severe pain or swelling at the injection site, chest pain, an irregular heartbeat, fainting, sudden weakness or numbness in the legs, difficulty passing urine, severe headache with vision changes, or signs of a serious allergic reaction.
Pregnancy and Lactation
Goserelin must not be used during pregnancy, as it may cause miscarriage or harm the baby. Women who could become pregnant should use reliable non-hormonal contraception (such as condoms or a copper coil) during treatment. It should not be used while breastfeeding.
Precautions and Warnings
- Bone density may be monitored; calcium, vitamin D and exercise help protect bones.
- Blood sugar, blood pressure, cholesterol and heart checks may be needed, especially in men on long-term treatment.
- Men at risk of spinal cord compression or urinary blockage need close monitoring at the start.
- Tell your doctor if you have depression, diabetes or heart disease.
- Periods usually stop during treatment; contraception is still needed.
Overdose
Overdose is unlikely because the implant is given by a health professional. If it occurs, treatment is supportive according to symptoms.
Therapeutic Class
Gonadotropin-releasing hormone (GnRH) agonist, hormonal antineoplastic
Storage
Store below 25°C in a dry place, in the sealed pouch, or as directed on the pack. Given by health professionals; keep out of the reach of children.
Prepared by the Oshud Alo team from standard drug references. For information only; always follow your doctor's advice.