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Nafarelin

(naf a' re lin)

Brand Name(s):

  • Synarel®

WHY is this medicine prescribed?

Nafarelin is a hormone used to treat symptoms of endometriosis such as pelvic pain, menstrual cramps, and painful intercourse. Nafarelin also is used to treat central precocious puberty (early puberty) in young boys and girls.

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

HOW should this medicine be used?

Nafarelin comes as a nasal spray. To use it, first clear your nasal passages by gently blowing your nose. Then insert the sprayer into a nostril. Sniff as you squeeze the sprayer once. To prevent mucus from entering the sprayer, release your grip after you remove the sprayer from your nose. Gently sniff two or three more times.

For treating endometriosis, initially nafarelin is used twice a day: one spray in one nostril in the morning and one spray in the other nostril in the evening. Nafarelin should be started between the second and fourth days of your menstrual period. Nafarelin should not be used for longer than 6 months to treat endometriosis.

For treating precocious puberty, initially nafarelin is used once a day as two sprays in each nostril each morning, for a total of four sprays each morning.

Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Nafarelin initially worsens symptoms before improving them. Use nafarelin exactly as directed. Do not use more or less of it or use it more often than prescribed by your doctor. Do not stop using nafarelin without talking to your doctor.

What SPECIAL PRECAUTIONS should I follow?

Before using nafarelin,

  • tell your doctor and pharmacist if you are allergic to nafarelin, gonadotropin-releasing hormones, or any other drugs.
  • tell your doctor and pharmacist what prescription and nonprescription medications you are taking, especially anticonvulsants to treat seizures or epilepsy, nasal decongestants, steroids, and vitamins.
  • tell your doctor if you have or have ever had osteoporosis or a family history of osteoporosis; ovarian cysts, ovarian tumors, or ovarian cancer; chronic rhinitis (runny nose); or a history of depression.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. It is important to use a non-hormonal means of contraception (birth control) while using nafarelin (e.g., condom or diaphragm). If you become pregnant while using nafarelin, call your doctor immediately.

What should I do IF I FORGET to take a dose?

Use the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not use a double dose to make up for a missed one.

If doses are missed, you may experience breakthrough menstrual bleeding. Do not be alarmed, but inform your doctor.

What SIDE EFFECTS can this medicine cause?

Nafarelin may cause side effects. Usually these symptoms are temporary, lasting only until your body adjusts to the medication. Tell your doctor if any of these symptoms are severe or do not go away:

  • acne
  • breast enlargement
  • vaginal bleeding (menstruation should stop with this medication)
  • mood swings
  • increase in pubic hair
  • body odor
  • seborrhea (skin irritation)
  • nasal irritation
  • headache
  • hot flashes
  • insomnia
  • change in weight
  • vaginal dryness or vaginal discharge
  • change in sex drive
  • oily skin
  • muscle aches
  • rhinitis (runny nose)
  • depression

If you experience any of the following symptoms, call your doctor immediately:

  • stomach pain not related to menstruation
  • shortness of breath or difficulty breathing
  • chest pain
  • rash
  • severe itching

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online ( Web Site ) or by phone (1-800-332-1088).

What should I know about STORAGE and DISPOSAL of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website ( Web Site) for more information if you do not have access to a take-back program.

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. Web Site

What should I do in case of OVERDOSE?

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at Web Site. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

What OTHER INFORMATION should I know?

If you must use a nasal decongestant, wait at least 2 hours after using the nafarelin spray.

Avoid sneezing or blowing your nose during or immediately after using nafarelin. This decreases nafarelin's effectiveness.

Keep all appointments with your doctor and the laboratory.

Do not let anyone else use your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

AHFS® Consumer Medication Information. © Copyright, The American Society of Health-System Pharmacists, Inc., 7272 Wisconsin Avenue, Bethesda, Maryland. All Rights Reserved. Duplication for commercial use must be authorized by ASHP.

Selected Revisions: June 15, 2018.