DESCRIPTION
MECHANISM OF ACTION
Administration leads to initial release of follicle-stimulating hormone (FSH) and luteinizing hormone (LH), followed by suppression of gonadotropin secretion as a result of desensitization of the pituitary to gonadotropin-releasing hormone. This results in decreased secretion of LH and FSH from the pituitary.
ABSORPTION
Not orally absorbed because of extensive proteolysis in the GI tract. Bioavailability of subcutaneously administered drug is 75%–90%.
DISTRIBUTION
Distribution is not well characterized. Slowly released over a 28-day period. Peak serum concentrations are achieved 10–15 days after drug administration. About 30% of goserelin is bound to plasma proteins.
INDICATIONS
Advanced prostate cancer.
DOSAGE RANGE
Administer 3.6 mg SC every 28 days or 10.8 mg SC every 90 days.
DRUG INTERACTIONS
None well characterized to date.
SPECIAL CONSIDERATIONS
1. Initiation of treatment with goserelin may induce a transient tumor flare. Goserelin should not be given in patients with impending ureteral
obstruction and/or spinal cord compression or in those with painful bone metastases.
2. Serum testosterone levels decrease to castrate levels within 2–4 weeks after initiation of therapy.
3. Use with caution in patients with abnormal renal function.
4. Caution patients about the potential for hot flashes. Consider the use of soy tablets, 1 tablet PO tid, for prevention and/or treatment.
TOXICITY 1
Hot flashes occur in 50% of patients, decreased libido (10%), impotence (10%), and gynecomastia (10%).
TOXICITY 2
Tumor flare. Occurs in up to 20% of patients, usually within the first 2 weeks of starting therapy, and presents as increased bone pain, urinary retention, or back pain with spinal cord compression. Usually prevented by pretreating with an antiandrogen agent such as flutamide, bicalutamide, or nilutamide.
TOXICITY 3
Local discomfort at the site of injection.
TOXICITY 4
Elevated serum cholesterol levels.
TOXICITY 5
Hypersensitivity reaction.
TOXICITY 6
Nausea and vomiting.
SPECIFICATION
Login To Comment