Compare Peptides

Select any two compounds for a side-by-side comparison of mechanism, uses, risks, and FDA regulatory status.

Popular comparisons

Leuprolide

Lupron, Eligard

FDA Approved
GnRH Agonist

Kisspeptin

Kisspeptin-54, Kisspeptin-10

Investigational
Hormonal & Reproductive
Overview

A synthetic GnRH agonist that paradoxically suppresses gonadotropin release with chronic use. One of the most commercially important peptide drugs, used in prostate cancer, endometriosis, precocious puberty, and fertility treatments.

A neuropeptide that acts as the master regulator of the reproductive hormone axis. Kisspeptin neurons in the hypothalamus control the release of GnRH (gonadotropin-releasing hormone), which in turn drives LH and FSH production. Increasingly studied for fertility treatment, hypogonadism, and as a diagnostic tool for reproductive disorders. Also being explored for its role in emotional and sexual brain processing.

Mechanism of Action

Initially stimulates LH and FSH release (flare effect), then downregulates GnRH receptors with continuous exposure, leading to profound suppression of testosterone and estrogen production. This 'chemical castration' effect is therapeutically useful.

Binds to the KISS1R (GPR54) receptor on GnRH neurons in the hypothalamus, triggering GnRH release. This stimulates the anterior pituitary to release LH and FSH, which drive testosterone production in males and ovulation in females. Kisspeptin is the upstream 'gatekeeper' of the entire HPG axis.

Common Uses
  • Prostate cancer treatment
  • Endometriosis
  • Uterine fibroids
  • Precocious puberty
  • Fertility treatments (IVF protocols)
  • Fertility treatment (investigational)
  • Hypogonadism evaluation
  • IVF protocols (as GnRH trigger alternative)
  • Reproductive endocrinology research
  • Libido and sexual function research
Known Risks
  • Hot flashes
  • Bone density loss with long-term use
  • Mood changes and depression
  • Initial testosterone flare (prostate cancer)
  • Injection site reactions
  • Cardiovascular risk with prolonged use
  • Injection site discomfort
  • Headache and flushing
  • Potential for ovarian hyperstimulation in women
  • Short half-life requires frequent dosing or infusion
  • Limited long-term safety data
Regulatory Status
FDA Approved

FDA-approved as Lupron/Lupron Depot (multiple indications since 1985) and Eligard. One of the highest-revenue peptide drugs historically. Available in 1-month, 3-month, 4-month, and 6-month depot formulations.

Investigational

Not FDA-approved. Active clinical trials at Imperial College London and other institutions for fertility applications. Being studied as a safer alternative to hCG triggers in IVF (lower risk of ovarian hyperstimulation syndrome). No US-approved formulation exists.

This comparison is for educational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional before starting any peptide therapy.