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Zoladex Dosage

Generic name: goserelin acetate 3.6mg
Dosage form: implant
Drug classes: Gonadotropin releasing hormones, Hormones / antineoplastics

Medically reviewed by Last updated on Mar 24, 2023.

ZOLADEX, at a dose of 3.6 mg, should be administered subcutaneously every 28 days into the anterior abdominal wall below the navel line using an aseptic technique under the supervision of a physician [see Dosage and Administration (2.7)].

While a delay of a few days is permissible, every effort should be made to adhere to the 28-day schedule.

Stage B2-C Prostatic Carcinoma

When ZOLADEX is given in combination with radiotherapy and flutamide for patients with Stage T2b-T4 (Stage B2-C) prostatic carcinoma, treatment should be started 8 weeks prior to initiating radiotherapy and should continue during radiation therapy. A treatment regimen using a ZOLADEX 3.6 mg depot 8 weeks before radiotherapy, followed in 28 days by the ZOLADEX 10.8 mg depot, can be administered. Alternatively, four injections of 3.6 mg depot can be administered at 28-day intervals, two depots preceding and two during radiotherapy.

Prostatic Carcinoma

For the management of advanced prostate cancer, ZOLADEX is intended for long-term administration unless clinically inappropriate.


For the management of endometriosis, the recommended duration of administration is 6 months.

Currently, there are no clinical data on the effect of treatment of benign gynecological conditions with ZOLADEX for periods in excess of 6 months.

Retreatment cannot be recommended for the management of endometriosis since safety data for retreatment are not available. If the symptoms of endometriosis recur after a course of therapy, and further treatment with ZOLADEX is contemplated, consideration should be given to monitoring bone mineral density. Clinical studies suggest the addition of Hormone Replacement Therapy (estrogens and/or progestins) to ZOLADEX is effective in reducing the bone mineral loss which occurs with ZOLADEX alone without compromising the efficacy of ZOLADEX in relieving the symptoms of endometriosis. The addition of Hormone Replacement Therapy may also reduce the occurrence of vasomotor symptoms and vaginal dryness associated with hypoestrogenism. The optimal drugs, dose and duration of treatment has not been established.

Endometrial Thinning

For use as an endometrial-thinning agent prior to endometrial ablation, the dosing recommendation is one or two depots (with each depot given four weeks apart). When one depot is administered, surgery should be performed at four weeks. When two depots are administered, surgery should be performed within two to four weeks following administration of the second depot.

Breast Cancer

For the management of advanced breast cancer, ZOLADEX is intended for long-term administration unless clinically inappropriate.

Renal or Hepatic Impairment

No dosage adjustment is necessary for patients with renal or hepatic impairment.

Administration Technique

The proper method of administration of ZOLADEX is described in the instructions that follow.

  1. Put the patient in a comfortable position with the upper part of the body slightly raised. Prepare an area of the anterior abdominal wall below the navel line with an alcohol swab.
    NOTE: Caution should be taken while injecting ZOLADEX into the anterior abdominal wall due to the proximity of underlying inferior epigastric artery and its branches.
  2. Examine the foil pouch and syringe for damage. Remove the syringe from the opened foil pouch and hold the syringe at a slight angle to the light. Check that at least part of the ZOLADEX implant is visible.
  3. Grasp the red plastic safety tab and pull away from the syringe, and discard. Remove needle cover. Unlike liquid injections, there is no need to remove air bubbles as attempts to do so may displace the ZOLADEX implant.
  4. Holding the syringe around the protective sleeve, using an aseptic technique, pinch the skin of the patient's anterior abdominal wall below the navel line. With the bevel of the needle facing up, insert the needle at a 30 to 45 degree angle to the skin in one continuous deliberate motion until the protective sleeve touches the patient's skin.
    NOTE: The ZOLADEX syringe cannot be used for aspiration. If the hypodermic needle penetrates a large vessel, blood will be seen instantly in the syringe chamber. If a vessel is penetrated, withdraw the needle and inject with a new syringe elsewhere. Monitor patients for signs or symptoms of abdominal hemorrhage. Use extra care when administering ZOLADEX to patients with a low BMI and/or to patients receiving full dose anticoagulation [see Warnings and Precautions (5.9)].
  5. Do not penetrate into muscle or peritoneum.
  6. To administer the ZOLADEX implant and to activate the protective sleeve, grasp the barrel at the finger grip and depress the plunger until you cannot depress it any further. If the plunger is not depressed fully, the protective sleeve will NOT activate. When the protective sleeve ‘clicks’, the protective sleeve will automatically begin to slide to cover the needle.
    NOTE: The needle does not retract.
  7. Withdraw the needle and allow protective sleeve to slide and cover needle. Dispose of the syringe in an approved sharps collector.

NOTE: In the unlikely event of the need to surgically remove ZOLADEX, it may be localized by ultrasound.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.