How is the Zoladex implant administered?

The Zoladex implant is a small biodegradable cylinder injected subcutaneously into the anterior abdominal wall using a pre-loaded syringe with a 16-gauge needle. The procedure takes seconds and is performed in a clinic. The implant dissolves over 28 days (3.6 mg) or 12 weeks (10.8 mg), continuously releasing goserelin.

What is the testosterone flare and how is it managed?

In the first 1-2 weeks of goserelin treatment, LH and testosterone levels temporarily rise (the "flare"), which can worsen prostate cancer symptoms including bone pain and urinary obstruction. This is typically prevented by starting an anti-androgen (e.g., bicalutamide or flutamide) 1-2 weeks before the first goserelin injection and continuing for 2-4 weeks.

Can goserelin be used for fertility treatment?

Goserelin is used off-label in IVF protocols for pituitary downregulation before controlled ovarian hyperstimulation. There is also evidence from the POEMS/SWOG S0230 trial (Moore et al., NEJM 2015, PMID: 25738669) that goserelin during chemotherapy may protect ovarian function and preserve fertility in premenopausal breast cancer patients.

What is the recommended dose range for Goserelin?

The research dose range is Prostate cancer: 3.6 mg q28d or 10.8 mg q12w. Breast cancer: 3.6 mg q28d. Endometriosis: 3.6 mg q28d for 6 months., administered via Subcutaneous implant (anterior abdominal wall), Every 28 days (3.6 mg) or every 12 weeks (10.8 mg).

peptide dosing

Goserelin Dosing & Reconstitution Guide

Complete dosing reference for Goserelin (Reproductive / Hormonal). Covers reconstitution, dose range, titration schedule, pharmacokinetics, and storage protocols for research use.

Dosing Protocol

Route: Subcutaneous implant (anterior abdominal wall) Frequency: Every 28 days (3.6 mg) or every 12 weeks (10.8 mg) Dose Range: Prostate cancer: 3.6 mg q28d or 10.8 mg q12w. Breast cancer: 3.6 mg q28d. Endometriosis: 3.6 mg q28d for 6 months.

Timeline & Pharmacokinetics

Onset: 2-4 weeks (hormonal suppression) Half-Life: ~4.2 hours Steady State: 2-4 weeks Time to Results: 2-4 weeks for castrate testosterone levels Washout: 4-12 weeks depending on implant

Storage

Lyophilized: Store below 25 °C (77 °F); do not freeze Reconstituted: Not applicable (pre-filled syringe/implant)

Safety & Contraindications

Safety: Hot flashes (up to 57-75% of patients) Decreased bone mineral density with prolonged use Initial disease flare (1-2 weeks): tumor flare in prostate cancer with potential spinal cord compression, bone pain exacerbation

Contraindications: Pregnancy (Category X/D depending on indication); Undiagnosed vaginal bleeding; Hypersensitivity to GnRH, GnRH agonist analogs, or PLGA

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Research Use Only. The information on this page is compiled from published research literature and is provided for educational purposes only. It does not constitute medical advice. All compounds referenced are intended for in vitro research use by qualified laboratories and institutions.