Nafarelin

Class: Gonadotropins
ATC Class: H01CA02
VA Class: HS900
Chemical Name: 6-[3-(2-naphthalenyl)-d-alanine]-hydrate acetate (salt) luteinizing hormone-releasing factor (pig)
Molecular Formula: C₆₆H₈₃N₁₇O₁₃•xC₂H₄O₂•yH₂O
CAS Number: 86220-42-0
Brands: Synarel

Medically reviewed by Drugs.com on Oct 6, 2021. Written by ASHP.

Introduction

Gonadotropin-releasing hormone (GnRH) agonist; synthetic decapeptide analog of GnRH (luteinizing hormone-releasing hormone, gonadorelin); structurally related to goserelin, leuprolide, and triptorelin.

Uses for Nafarelin

Endometriosis

Palliative treatment of endometriosis (e.g., pain relief, reduction in endometrial lesions). Experience limited to women ≥18 years of age treated for 6 consecutive months.

Precocious Puberty

Treatment of central (via activation of the hypothalamic-pituitary-gonadal axis) precocious puberty (true precocious puberty, GnRH-dependent precocious precocity, complete isosexual precocity) in children of both sexes (designated as an orphan drug by FDA for this use).

Nafarelin Dosage and Administration

General

• Delay administration of topical decongestants for ≥2 hours after nafarelin administration.

Endometriosis

• Exclude pregnancy prior to initiating therapy.

• Initiate treatment between days 2–4 of the menstrual cycle.

• Ovulation may not be suppressed at recommended dosage; use of an effective nonhormonal method of contraception is essential.

• If menstrual bleeding continues after first 2 months, consider lack of compliance. If compliance problems excluded, may increase dosage. (See Dosage: Endometriosis under Dosage and Administration.)

Precocious Puberty

• Evaluate bone age and growth velocity within 3–6 months of nafarelin initiation and periodically thereafter.

• If lack of suppression of the pituitary-gonadal axis, consider noncompliance with the treatment regimen. Recommend dosing be done by caregivers. If compliance problems excluded, reconsider possibility of gonadotropin-independent sexual precocity. If both are excluded, may increase dosage. (See Dosage: Precocious Puberty under Dosage and Administration.)

Administration

Intranasal Inhalation

Administer by nasal inhalation using a metered spray pump.

Avoid sneezing during or immediately after administration.

Prior to initial use, prime the nasal inhaler. To prime, hold bottle upright and quickly depress the side arms of pump toward the bottle 7–10 times, until a fine spray occurs.

Clear nasal passages prior to administration.

Tilt the head slightly backward, insert the spray tip into one nostril, and point the tip toward the back of the nose. Rapidly and firmly press and actuate into the nostril while holding the other nostril closed and concurrently inspire through the nose. After removing the spray tip from the nostril, remain with head tilted backward for a few seconds. If additional sprays .