nafarelin

Contraindicated in:

Hypersensitivity to GnRH, its analogues, or sorbitol;
OB: Pregnancy ;
Lactation: Lactation.

Use Cautiously in:

Rhinitis;
Seizures, cerebrovascular disorders, or CNS tumor (may ↑ risk of seizures).

Adv. Reactions/Side Effects ⬆ ⬇

CV: edema, MI

Derm: acne, hot flushing, hirsutism, seborrhea

EENT: nasal irritation

Endo: ↓breast size, hyperglycemia

GU: ↓fertility, ↓libido, cessation of menses, vaginal dryness

Metab: weight gain

MS: ↓bone density, myalgia

Neuro: headache, aggression, anger, depression, impatience, insomnia, intracranial hypertension (children), irritability, SEIZURES, STROKE, SUICIDAL ATTEMPT/IDEATION (CHILDREN)

Misc: hypersensitivity reactions

Interactions ⬆ ⬇

Drug-drug:

Topical nasal decongestants may ↓ absorption (administer decongestant ≥2 hr after nafarelin).
Bupropion or SSRIs may ↑ risk of seizures.

Availability ⬆ ⬇

Nasal spray: 2 mg/mL (200 mcg/spray)

Route/Dosage ⬆ ⬇

Endometriosis

Intranasal (Adults ): One spray (200 mcg) in one nostril in the morning and one spray in the other nostril in the evening (400 mcg/day). May ↑ to one spray in each nostril in the morning and evening (800 mcg/day).

Central Precocious Puberty

Intranasal (Children ): Two sprays in each nostril in the morning and in the evening (1600 mcg/day); may ↑ up to 1800 mcg/day (three sprays in alternating nostrils three times daily).

US Brand Names ⬆ ⬇

Action ⬆ ⬇

Acts as a synthetic analogue of gonadotropin-releasing hormone (GnRH). Initially increases pituitary production of luteinizing hormone and follicle-stimulating hormone, which cause ovarian steroid production. Chronic administration leads to decreased production of gonadotropins. Endometriotic lesions are sensitive to ovarian hormones.

Therapeutic effects:

Reduction in lesions and associated pain in endometriosis.
Arrest and regression of puberty in children with central precocious puberty.

Classifications ⬆ ⬇

Therapeutic Classification: hormones

Pharmacologic Classification: gonadotropin releasing hormones

Pharmacokinetics ⬆ ⬇

Absorption: Well absorbed following intranasal administration.

Distribution: Unknown.

Metabolism/Excretion: 20–40% excreted in feces; 3% excreted unchanged by the kidneys.

Half-Life: 3 hr.

Time/Action Profile ⬆ ⬇

(↓ ovarian steroid production)

ROUTE		ONSET		PEAK		DURATION
Intranasal		within 4 wk		3–4 wk		3–6 mo‡

‡Relief of symptoms of endometriosis following discontinuation.

Patient/Family Teaching ⬆ ⬇

Explain purpose and side effects of medication. Advise patient to read Patient Information before starting therapy.
Instruct patient on correct technique for nasal spray: Tilt head back slightly; wait 30 sec between sprays. Inform patient and caregiver that if doses are not taken as directed, pubertal process may be reactivated when treating central precocious puberty.
- Advise patient to notify health care provider if rhinitis occurs and if a topical decongestant is needed; do not use decongestant until 2 hr after nafarelin dose. If possible, avoid sneezing during and immediately after dose is administered.
- Advise patient that medication may cause hot flashes. Notify health care provider if persistent or bothersome.
Advise patient to notify health care provider of all Rx or OTC medications, vitamins, or herbal products being taken and to consult health care provider before taking other medications.
Inform patients with endometriosis that amenorrhea is expected and to notify health care provider if regular menstruation persists or if successive doses are missed.
Rep: May cause fetal harm. Advise women of reproductive potential to use a form of contraception other than oral contraceptives and to avoid breastfeeding during therapy.
Advise patient and caregiver that some signs of puberty (vaginal bleeding, breast enlargement) may occur and should resolve after 1st mo of therapy. If these signs persist after 2nd mo of therapy, notify health care provider.

Pronunciation ⬆ ⬇

Code ⬆

NDC Code

0025- Pfizer Laboratories Div Pfizer Inc
- 0025-0166- Synarel
  - 0025-0166-08- 1 BOTTLE, SPRAY in 1 CARTON (0025-0166-08) / 8 mL in 1 BOTTLE, SPRAY

12869- Corden Pharma Colorado, Inc.
- 12869-731-
  - 12869-731-01- 300 g in 1 BOTTLE (12869-731-01)

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Indications ⬇

Contraind./Precautions ⬆ ⬇