Overview
Leuprolide (leuprorelin) is a synthetic GnRH agonist nonapeptide approved by the FDA under the brand name Lupron for advanced prostate cancer, endometriosis, uterine fibroids, and central precocious puberty. It is one of the most widely used GnRH analogs globally. Available as daily subcutaneous injection or long-acting depot formulations releasing drug over 1, 3, 4, or 6 months, it achieves profound sex steroid suppression through pituitary desensitization.
Mechanism of action
Leuprolide is a potent GnRH receptor agonist with roughly 100 times the receptor affinity of endogenous GnRH. Initial administration stimulates pituitary gonadotrophs, causing an LH and FSH surge ('flare') lasting 1–2 weeks. With continuous administration, persistent non-pulsatile receptor stimulation causes GnRH receptor downregulation and pituitary desensitization. LH and FSH secretion falls to castrate levels within 2–4 weeks, reducing testosterone in men to <50 ng/dL and estradiol in women to postmenopausal levels. This medical castration effect is fully reversible upon discontinuation. In prostate cancer, testosterone suppression removes the androgen stimulus that drives tumor proliferation, inducing cancer cell apoptosis.
Dosing protocols
| Purpose | Route | Dosage | Frequency | Notes |
|---|---|---|---|---|
| Advanced prostate cancer — ADT | intramuscular | 7.5–22.5 mg | every 1–3 months (depot) | 7.5 mg monthly, 22.5 mg every 3 months, 30 mg every 4 months, or 45 mg every 6 months. Add antiandrogen for first 4 weeks to prevent flare. |
| Endometriosis or uterine fibroids | intramuscular | 3.75–11.25 mg | monthly or every 3 months (depot) | 3.75 mg monthly or 11.25 mg every 3 months. Maximum 6 months. Often combined with norethindrone acetate 5 mg/day to limit bone loss. |
| Daily subcutaneous injection (non-depot) | subcutaneous | 1–1 mg | once daily | Used in specific clinical scenarios; depot formulations preferred for adherence. |
Dosing information is for educational purposes only. Consult a qualified healthcare professional before using any peptide.
Research summary
Decades of trials establish leuprolide depot as the standard androgen deprivation therapy (ADT) for advanced and metastatic prostate cancer, achieving castrate testosterone levels in >97% of patients. For endometriosis, 6-month courses reduce lesion volume and pelvic pain scores significantly versus placebo. The central precocious puberty indication is supported by long-term data demonstrating restoration of normal pubertal timing and final adult height. The depot formulations achieve equivalent clinical outcomes to daily injection with improved adherence. Long-term ADT is associated with metabolic side effects including bone loss, sarcopenia, and cardiovascular risk.
Side effects
Side effects vary by individual. This is not an exhaustive list. Report unusual symptoms to a healthcare professional.
Common stacks
Peptides commonly paired with Leuprolide for synergistic effects.
Legal status
FDA-approved for: palliative treatment of advanced prostate cancer; endometriosis; uterine leiomyomata (preoperative); and central precocious puberty. Multiple NDA approvals spanning 1985–2019. Prescription-only. Generic versions available since patent expiration.
Where to get it
Prescription required
Leuprolide is a prescription medication. Consult your healthcare provider or a licensed telehealth platform for access.