Goserelin acetate
Goserelin acetate (Zoladex)
Goserelin acetate
( GO-seh-rel-in)
Pregnancy Category: X (when used for endometriosis); D (when used for breast cancer) Zoladex Zoladex LA (Rx)

Classification: Antineoplastic, hormonal agent

See Also: See also Antineoplastic Agents .

Action/Kinetics: Goserelin acetate is a synthetic decapeptide analog of LHRH (or GnRH) which is a potent inhibitor of gonadotropin secretion from the pituitary gland. Initially, there is actually an increase in serum luteinizing hormone and FSH. This is followed by a long-term suppression of pituitary gonadotropins with serum levels of testosterone decreasing to those seen in surgically castrated males. When used for endometriosis, the drug controls the secretion of hormones required for the ovary to synthesize estrogen resulting in plasma estrogen levels seen in menopause. Peak serum levels after SC implantation of 3.6 mg: 12-15 days. Mean peak serum levels: Approximately 2.5 ng/mL. Available as an implant in a preloaded syringe. For the first 8 days of the treatment cycle, the rate of absorption of the 3.6 mg implant is slower than for the remainder of the period. For the 10.8 mg depot, mean levels increase to a peak within the first 24 hr and then decline rapidly until day 4; thereafter, mean levels remain constant until the end of the treatment period. t 1/2, elimination: 4.2 hr for normal renal function and 12.1 hr for C _CR less than 20 mL/min. Rapidly cleared by a combination of hepatic metabolism and urinary excretion.

Uses: Implant, 3.6 mg or 10.8 mg: Palliative treatment of advanced prostatic carcinoma as an alternative to orchiectomy or estrogen administration when these are either unacceptable to the client or not indicated. With flutamide (Eulexin) prior to (start 8 weeks before) and during radiation therapy to treat early stage B2-C prostatic carcinoma. Implant, 3.6 mg only: Endometriosis, including pain relief and reduction of endometriotic lesions. Palliative treatment of advanced breast cancer in premenopausal and postmenopausal women. For endometrial thinning prior to ablation for dysfunctional uterine bleeding.

Contraindications: Pregnancy, lactation, nondiagnosed vaginal bleeding, hypersensitivity to LHRH or LHRH agonist analogs. Use of the 10.8-mg implant in women.

Special Concerns: Safety and effectiveness have not been determined in clients less than 18 years of age. There may be transient worsening of symptoms during the first few weeks of therapy. Use with caution in males who are at particular risk of developing ureteral obstruction or spinal cord compression.

Side Effects: In males. GU: Sexual dysfunction, decreased erections, lower urinary tract symptoms, gynecomastia, renal insufficiency, urinary obstruction, UTI, bladder neoplasm, hematuria, impotence, urinary frequency, incontinence, urinary tract disorder, impaired urination. CV: CHF, CVA, MI, heart failure, pulmonary embolus arrhythmia, hypertension, peripheral vascular disorder, chest pain, angina pectoris, cerebral ischemia, varicose veins. CNS: Lethargy, dizziness, insomnia, asthenia, anxiety, depression, headache, paresthesia. GI: N&V;, diarrhea, constipation, ulcer, anorexia, hematemesis. Respiratory: URI, COPD, increased cough, dyspnea, pneumonia. Metabolic: Gout, hypercalcemia, weight increase, diabetes mellitus. Miscellaneous: Pelvic or bone pain, anemia, chills, fever, breast pain, breast swelling or tenderness, abdominal or back pain, flu syndrome, sepsis, aggravation reaction, herpes simplex, pruritus, peripheral edema, injection site reaction, hot flashes, rash, sweating, complications of surgery, hypersensitivity, pain, edema.
In females. GU: Vaginitis, decreased or increased libido, pelvic symptoms, dyspareunia, dysmenorrhea, urinary frequency, UTI, vaginal bleeding (during the first 2 months) of varying duration and intensity. CV: Hemorrhage hypertension, palpitations, migraine, tachycardia. CNS: Emotional lability, depression, headache, insomnia, dizziness, nervousness, anxiety, paresthesia, somnolence, abnormal thinking, malaise, fatigue, lethargy. GI: N&V;, abdominal pain, increased appetite, anorexia, constipation, diarrhea, dry mouth, dyspepsia, flatulence. Musculoskeletal: Asthenia, back pain, myalgia, hypertonia, arthralgia, joint disorder, decrease of vertebral trabecular bone mineral density. Dermatologic: Sweating, acne, seborrhea, hirsutism, pruritus, alopecia, dry skin, ecchymosis, rash, skin discoloration, hair disorders. Respiratory: Pharyngitis, bronchitis, increased cough, epistaxis, rhinitis, sinusitis. Ophthalmic: Amblyopia, dry eyes. Miscellaneous: Hot flashes, breast atrophy or enlargement, breast pain, tumor flare, pain, infection, application site reaction, flu syndrome, voice alterations, weight gain, allergic reaction, chest pain, fever, peripheral edema, hypercalcemia, osteoporosis, hypersensitivity.

Laboratory Test Alterations: LDL and HDL cholesterol, triglycerides, AST, ALT. Misleading results of pituitary-gonadotropic and gonadal function tests that are conducted during treatment.

How Supplied: Implant: 3.6 mg , 10.8 mg

Dosage
?SC Implant, 3.6 mg Prostatic carcinoma, endometriosis, advanced breast cancer, thinning prior to endometrial ablation for dysfunctional uterine bleeding.
3.6 mg q 28 days into the upper abdominal wall using sterile technique under the direction of a physician.
?SC Implant, 10.8 mg Advanced prostatic carcinoma.
10.8 mg q 12 weeks into the upper abdominal wall using sterile technique under the direction of a physician.
With flutamide to treat Stage B2-C prostatic carcinoma.
One goserelin 3.6 mg depot followed in 28 days by one 10.8 mg depot.