nafarelin acetate: clinical use

Prescribing considerations

• Exclude pregnancy and counsel about non-hormonal barrier contraception where appropriate.
• Assess adherence and nasal-spray technique; missed administrations may permit breakthrough ovulation.
• Discuss the initial hormonal flare and possible temporary worsening of endometriosis symptoms.
• Use caution in polycystic ovarian disease and during ovarian stimulation because of excessive follicular recruitment, ovarian cysts and OHSS.
• Review bone-health risk before considering further exposure.
• Warn about depression and arrange assessment if mood symptoms develop.
• Consider persistent nasal mucosal swelling related to benzalkonium chloride.

Contraindications and cautions

• Hypersensitivity to GnRH, GnRH agonist analogues or product excipients
• Undiagnosed vaginal bleeding
• Pregnancy or possible pregnancy during treatment
• Breastfeeding

Monitoring

• Clinical response and abnormal vaginal bleeding
• Mood and symptoms of depression
• Signs of ovarian cyst formation or OHSS during fertility treatment
• Bone density when further treatment is being considered
• Nasal mucosa and spray performance
• Interpret pituitary-gonadal tests cautiously during and following suppression

Clinical pharmacology

Nafarelin is a potent GnRH agonist. Initial gonadotrophin stimulation is followed by pituitary desensitisation, reduced biologically active LH and FSH, and suppression of gonadal steroidogenesis. Intranasal systemic bioavailability is low, and degradation occurs mainly through peptidases rather than cytochrome P450 enzymes.

Formulation and product differences

• The selected product is a clear aqueous metered nasal-spray solution.
• It contains benzalkonium chloride, which may irritate or swell the nasal mucosa, particularly with prolonged exposure.
• The spray pump requires first-use priming and regular tip cleaning to maintain accurate delivery.
• Pack sizes and bottle materials may vary, and not all presentations may be marketed.