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This platform provides peer-reviewed research summaries and educational content about peptides for wellness and optimization purposes. Nothing on this site is intended as medical advice, diagnosis, or treatment. We do not claim any peptide can diagnose, treat, cure, or prevent any disease. Always consult a licensed healthcare provider before beginning any wellness protocol.

Statements on this site have not been evaluated by the FDA. Compounded preparations are subject to applicable state and federal regulations. Availability and eligibility vary.

GnRH Agonist · Endocrine

Nafarelin (Synarel)

Intranasal GnRH agonist for endometriosis and central precocious puberty.

FDA-Approved

Plain-Language Label Highlights

Brand names: Synarel

What it's approved for

Endometriosis and central precocious puberty.

A nasal spray version of a GnRH agonist that lowers sex hormones to ease endometriosis pain or pause early puberty.

Common side effects
  • Hot flashes
  • Vaginal dryness
  • Decreased libido
  • Headache
  • Nasal irritation
Serious risks to know
  • Bone density loss with prolonged use
  • Mood changes
  • Initial hormone flare
Who should avoid or use with extra caution
  • Pregnancy
  • Undiagnosed abnormal vaginal bleeding
  • Known hypersensitivity to GnRH analogs

Educational summary of the FDA prescribing information. Not a substitute for the full label or medical advice. Always discuss with a licensed prescriber.

Mechanism of Action

Decapeptide GnRH agonist administered intranasally; sustained receptor occupancy downregulates pituitary GnRH receptors, suppressing gonadotropin and sex steroid output.

Research Areas

Endometriosis
Central precocious puberty

Common Research Protocols

Intranasal

200 mcg per spray; one spray in each nostril twice daily for endometriosis.

Protocols summarized for educational reference from published research. Not dosing guidance.

Cited Research

[1]Fertility & Sterility·1990

Nafarelin for endometriosis

Comparable pain and lesion reduction to danazol with different side-effect profile.

Important Considerations

  • FDA-approved.
  • Hypoestrogenic symptoms; limit treatment course for bone health.

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Educational Information Only — Not Medical Advice

All content on this page is for educational and informational purposes only. It is not medical advice, diagnosis, or treatment. We make no claims that any peptide can diagnose, treat, cure, or prevent any disease. Peptides discussed are not FDA-approved for the indications listed unless explicitly stated otherwise.

Always consult a licensed healthcare provider before beginning any wellness protocol. Statements have not been evaluated by the FDA. Compounded preparations are subject to applicable state and federal regulations. Availability, eligibility, and pricing may vary.

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