Goserelin

Goserelin is a prescription hormonal implant used to treat prostate cancer and breast cancer. It is also used for other conditions unrelated to cancer such as endometriosis and abnormal bleeding of the uterus. Goserelin implant is in a class of medications called gonadotropin-releasing hormone (GnRH) agonists. It works by decreasing testosterone production in men and estrogen production in women.

This medication comes in the form of an implant that is inserted just under the skin of the stomach every 4 weeks or every 12 weeks, depending on what is being treated. The implant will be inserted by a healthcare professional. 

Common side effects of goserelin include hot flashes, sexual dysfunction, and headaches.

Goserelin can also cause dizziness and/or drowsiness. Do not drive or operate heavy machinery until you know how this medication affects you.

Goserelin is a prescription hormonal implant medication used:

• with flutamide to treat locally confined prostate cancer
• to treat advanced prostate cancer
• to manage endometriosis
• as an endometrial-thinning agent prior to endometrial ablation for dysfunctional uterine bleeding
• to treat advanced breast cancer

This medication may be prescribed for other uses. Ask your doctor or pharmacist for more information.

Goserelin may be found in some form under the following brand names:

• Zoladex

Serious side effects have been reported with goserelin. See the “Drug Precautions” section.

Common side effects of goserelin include the following:

• hot flashes
• headaches
• depression
• acne
• tiredness
• dizziness
• insomnia

This is not a complete list of goserelin side effects. Ask your doctor or pharmacist for more information.

Tell your doctor if you have any side effect that bothers you or that does not go away.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

No formal drug interactions have been performed by the manufacturer. However, you should tell your doctor about all the medicines you take including prescription and non-prescription medicines, vitamins, and herbal supplements. Not all drug interactions are known or reported and new drug interactions are continually being reported.

Serious side effects have been reported with goserelin including the following:

Tumor flare phenomenon. Temporary worsening of tumor symptoms may occur during the first few weeks of treatment with goserelin, which may include difficulty urinating and spinal cord compression. Consult with your physician about your level of risk for developing tumor flare phenomenon.

Severe allergic reactions. Severe and potentially life-threatening allergic reactions have been reported with the goserelin. Seek emergency medical attention immediately if you develop any of the following symptoms of a severe allergic reaction.

•  sudden difficulty breathing
•  sudden abnormal swelling of the face, lips, and/or throat
•  sudden onset of a red blister-like skin rash
•  sudden drop in blood pressure

High blood sugar and diabetes. Hyperglycemia (high blood sugar) and an increased risk of developing diabetes have been reported in men receiving medications similar to goserelin. Consult with your physician about your level of risk for developing hyperglycemia or diabetes during treatment with goserelin.

Heart disease. Increased risk of heart attack, sudden cardiac death, and stroke has been reported in association with use of medications similar to goserelin. Your physician will perform a comprehensive medical assessment of your risk for developing cardiovascular diseases during treatment with goserelin.

High levels of calcium. Elevated levels of calcium in the blood have been reported in certain patients receiving goserelin. Your physician will monitor your levels of blood calcium during your course of treatment.

Injection site injury. Injection site injury and blood vessel injury including pain, hematoma, bleeding, and severe bleeding requiring blood transfusions and surgical intervention has been reported in patients using goserelin. Consult with your physician about your level of risk for developing these complications during administration of goserelin.

Prolonged QT/QTc Interval. Your doctor will monitor you your heart.  

Goserelin can also cause dizziness and/or drowsiness. Do not drive or operate heavy machinery until you know how goserelin affects you.

Do not receive goserelin if you:

• are allergic to goserelin or to any of its ingredients 
• are pregnant, unless you have received specific instructions from your physician to take goserelin while you are pregnant

Medicines can interact with certain foods. In some cases, this may be harmful and your doctor may advise you to avoid certain foods. In the case of goserelin there are no specific foods that you must exclude from your diet when receiving goserelin.

Before receiving this medication, tell your doctor about all of your medical conditions. Especially tell your doctor if you:

• are allergic to goserelin or to any of its ingredients
• have diabetes
• have heart disease
• have hypercalcemia (high levels of calcium in your blood)
• have abnormal heart rhythms
• have osteoporosis
• have depression
• are pregnant or plan to become pregnant
• are breastfeeding or plan to breastfeed

Tell your doctor about all the medicines you take including prescription and non-prescription medicines, vitamins, and herbal supplements.

Tell your doctor if you are pregnant or plan to become pregnant.

The FDA categorizes medications based on safety for use during pregnancy. Five categories - A, B, C, D, and X, are used to classify the possible risks to an unborn baby when a medication is taken during pregnancy.

Goserelin falls into category X. This medication should not be taken during pregnancy as it may harm the unborn baby. In animal studies, pregnant animals were given this medication and had some babies born with problems.

Tell your doctor if you are breastfeeding or plan to breastfeed.

It is not known if goserelin is excreted in human breast milk or if it will harm your nursing baby.

Use goserelin exactly as prescribed.

• Goserelin comes in an injectable implant form to be inserted directly under the skin of the stomach, typically every 4 weeks or every 12 weeks depending on what is being treated.
• Goserelin will be typically administered by a healthcare professional in a clinic or doctor's office.
• You are not likely to be able to feel the implant through your skin, and it should not cause pain or discomfort. The implant will dissolve in your body over time.
• If you are a premenopausal woman, you should stop having menstrual periods during treatment with goserelin. Call your doctor if you still have regular periods. Missing a dose can cause breakthrough bleeding.
• While your hormone levels are adjusting to this medication, you may notice increased symptoms or new symptoms of your condition. This should be only temporary during the first few weeks of treatment. Tell your doctor if your symptoms do not improve after several weeks of using goserelin.
• Your blood sugar may need to be checked while using goserelin, even if you are not diabetic. You may need other blood tests at your doctor's office. Visit your doctor regularly.
• This medication can cause you to have unusual results with certain medical tests. Tell any doctor who treats you that you are using goserelin.
• Keep all appointments with your doctor. Laboratory and/or medical tests (such as blood sugar, hormone levels) should be performed periodically to monitor your progress or check for side effects. 
• If you miss an appointment to receive your next dose, reschedule the appointment as soon as you remember. In women, sudden/unusual vaginal bleeding (breakthrough bleeding) may occur if a dose is missed.

If overdose is suspected, call your local Poison Control Center or seek emergency medical attention right away.