What is Zoladex (goserelin)?
Zoladex, also known as goserelin, is a prescription medication used in the treatment of various conditions influenced by hormones. It belongs to a class of drugs called gonadotropin-releasing hormone (GnRH) agonists. Zoladex works by suppressing the production of certain hormones in the body, such as estrogen or testosterone. It is commonly used in the treatment of prostate cancer, breast cancer, endometriosis, and certain gynecological disorders. Zoladex is administered via subcutaneous implant, typically placed under the skin of the abdomen, and provides a slow and continuous release of the medication over a specified period. The treatment duration and dosage may vary depending on the specific condition being treated. Regular monitoring and consultation with a healthcare professional are important for optimal management and potential side effects.

Prescription Required.
Product of Canada.
Shipped from Canada.
Prescription Required. | Product of Canada. | Shipped from Canada. |
What is Zoladex (goserelin)?
Zoladex is an implant medication prescribed for the treatment of breast cancer and endometriosis in women and prostate cancer in men. Zoladex is administered under the skin by a healthcare provider.
Zoladex belongs to the drug class, antineoplastics, classified as a gonadotropin-releasing hormone agonist (GnRH). These medications work by targeting and reducing certain hormones such as estrogen and testosterone.
What are the Indications for Zoladex?
In women, Zoladex is used to reduce and manage symptoms of breast cancer in patients who are perimenopausal or premenopausal. Zoladex may also be used to manage endometriosis symptoms as well as to treat endometriosis by thinning the lining of the uterus.
In men, Zoladex is used in combination with flutamide to manage locally confined prostate cancer. Zoladex may also be used to manage symptoms of advanced prostate cancer.
Zoladex is not recommended if you are allergic to Zoladex, have a known hypersensitivity to GnRH or GnRH agonist analogs, or have any sensitivity to any ingredients in Zoladex.
How is Zoladex used?
Storage
Zoladex will be stored by your healthcare provider. Zoladex should be stored in a cool, dry place below 25°C.
Instruction
Zoladex will be administered by your healthcare provider as follows:
- Clean the targeted abdomen area with alcohol.
- Remove the syringe from the storage pouch and inspect for any damage.
- Pinch the targeted abdomen skin and hold the needle at a 30° to 45° angle.
- Inject the needle until the sleeve touches the abdomen skin.
- Depress the plunger until you hear a “click”.
- Withdraw the needle and dispose of in an approved sharps container.
Dosage
Zoladex is available as an injectable implant form in the following strengths: 3.6 mg and 10.8 mg.
Zoladex is an implant that will be injected into your skin in the abdomen area either every 3 months or every 28 days depending on your treatment plan. The implant will slowly release the medication into your body until it is time for your next injection.
It is important to keep your appointments and reschedule any missed appointments as soon as possible. Missing appointments could result in a lapse between treatments and result in your cancer growing quicker.
Side Effects
It’s important to understand that although Zoladex is FDA-approved, it comes with side effects that may or may not affect you.
Before starting Zoladex, you should discuss possible side effects with your doctor or pharmacist.
Common Side Effects
Not all side effects require medical attention. As your body adjusts to Zoladex, side effects may go away.
Tell your doctor if you experience the following symptoms, and they become severe or do not go away on their own:
- Swelling at the injection site
- Dizziness
- Headache
- Hot flashes/flushing
- Increased sweating
- Nausea
- Difficulty sleeping
- Hair loss
- Vaginal dryness
- Change in breast sizes
- Change in testicle sizes
- Decreased sexual interest
Serious Side Effects
Severe adverse reactions while taking Zoladex can occur. Contact your doctor immediately, seek emergency medical care or call 911 if you experience any of the following symptoms:
- Severe allergic reaction: severe rash or itching, swelling in the face, lips, tongue, or throat, rapid heartbeat, fainting or dizziness, or problems breathing or swallowing.
- Stomach pain or swelling
- Mental disruption (hallucinations, depression, mood swings, etc.)
- Pain during intercourse for women
- Breast pain or tenderness
- Bone pain or broken bone
- Burning feeling in vagina
- Burning feeling in feet or toes
- Severe back pain
- Blood in urine
- Painful or difficulty urinating
- Stroke or heart attack
The information above does not list all possible side effects. Contact your doctor or pharmacist if you experience any side effects not listed. You or your doctor may report side effects to the FDA by calling 1-800-FDA-1088.
Warnings & Precautions
Before taking Zoladex, tell your doctor or pharmacist:
- If you are allergic to any medications such as Zoladex or any ingredients in Zoladex
- If you have or have had a known hypersensitivity to GnRH or GnRH agonist analogs
- If you have or have had diabetes
- If you have or have had bone loss or a family history of bone loss (osteoporosis)
- If you have or have had unexplained vaginal bleeding
- If you have or have had heart disease including heart attacks
- If you have or have had high cholesterol
- If you have or have had a stroke
- If you have or have had urinary blockage issues in men
- If you have or have had spinal cord issues in men
- If you are or plan to become pregnant
- If you are or plan to breastfeed
Diabetes
Taking Zoladex can fluctuate your blood sugar making it harder to control. Consult with your doctor regularly while taking Zoladex to keep your blood sugar levels under control. Your doctor may have to adjust your diabetes care treatment while you’re taking Zoladex.
Hypercalcemia
Taking Zoladex may cause you to have hypercalcemia where you have higher levels of calcium in your blood than normal. Your doctor will monitor and provide treatment, as necessary.
QT Prolongation
Taking Zoladex may increase your risk for QT prolongation resulting in irregular or fast heartbeats, especially if you are already taking other medications that put you at risk for QT prolongation. Taking Zoladex can also increase your risk if you have, have had, or have a family history of heart problems.
Though rare, QT prolongation can cause serious symptoms requiring immediate medical attention including severe irregular heartbeats, dizziness, and fainting. Consult with your doctor if you have any symptoms or concerns.
Pregnant or Planning to Become Pregnant
Taking Zoladex while pregnant is not recommended and can harm your unborn baby. Consult with your doctor on non-hormonal birth control options before using Zoladex. If you plan on becoming pregnant after taking Zoladex, wait 12 weeks after the last dose or until your period starts again to attempt to conceive.
Breastfeeding or Planning to Breastfeed
Taking Zoladex while breastfeeding is not recommended. There is not enough research to show if Zoladex will pass onto breastmilk and its implications to the infant. Consult with your healthcare provider before starting Zoladex.
Interactions & Contraindications
Before taking Zoladex, inform your doctor or pharmacist if you take any medications, herbal supplements, or vitamins. Currently, there are no known drug interactions with Zoladex and other medications.