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Generic Name: nafarelin nasal (NAF a REL in)
Brand Name: Synarel

What is Synarel (nafarelin nasal)?

Nafarelin nasal is a man-made form of a protein that is like a hormone in the body that helps regulate the menstrual cycle, fertility, and sexual development during puberty.

Nafarelin nasal is used to treat precocious puberty in both male and female children. It is also used to treat endometriosis in women who are 18 years of age or older.

Nafarelin nasal may also be used for purposes not listed in this medication guide.

What is the most important information I should know about Synarel (nafarelin nasal)?

Nafarelin nasal can harm an unborn baby or cause birth defects. Do not use if you are pregnant.

Do not breast-feed while using this medication.

If you are a woman, you should not use nafarelin nasal if you have abnormal vaginal bleeding that has not been checked by a doctor.

What should I discuss with my healthcare provider before using Synarel (nafarelin nasal)?

You should not use this medicine if you are allergic to nafarelin or similar medicines such as leuprolide (Lupron, Eligard, Viadur), goserelin (Zoladex), histrelin (Vantas), or triptorelin (Trelstar).

If you are a woman, you should not use nafarelin nasal if you have:

  • abnormal vaginal bleeding that has not been checked by a doctor; or

  • if you are pregnant or breast-feeding.

To make sure nafarelin nasal is safe for you, tell your doctor if you have:

  • diabetes, heart disease, high blood pressure, recent weight gain, high cholesterol (especially in men);

  • polycystic ovary disease;

  • low bone mineral density;

  • a personal or family history of osteoporosis;

  • sneezing or a runny nose;

  • a condition for which you take steroids or seizure medication; or

  • if you smoke or drink large amounts of alcohol.

Nafarelin nasal can harm an unborn baby or cause birth defects. Do not use nafarelin nasal if you are pregnant. Tell your doctor right away if you become pregnant during treatment.

Use a barrier form of birth control (condom or diaphragm with spermicide). Hormonal contraception (birth control pills, injections, implants, skin patches, and vaginal rings) may not be effective enough to prevent pregnancy during your treatment.

It is not known whether nafarelin nasal passes into breast milk or if it could harm a nursing baby. Do not breast-feed while using this medication.

How should I use Synarel (nafarelin nasal)?

Follow all directions on your prescription label. Do not use this medicine in larger or smaller amounts or for longer than recommended.

Do not miss any doses of this medicine. Skipping doses or not using nafarelin nasal correctly may cause a hormonal imbalance that could lead to unwanted side effects.

Nafarelin nasal is usually given 2 times per day, or once every 12 hours. Use the medicine at the same times each day.

Before your first use, prime the spray bottle by pumping it 5 to 10 times until a fine spray appears.

To use the nasal spray:

  • Blow your nose gently. Keep your head upright and insert the tip of the bottle into one nostril. Press your other nostril closed with your finger. Breathe in quickly and gently spray the medicine into your nose.

  • Tilt your head back for a few seconds to allow the medicine to flow to the back of your nose. Try not to sneeze right after using the nasal spray.

  • If you use more than one spray, wait at least 30 seconds before using the second spray.

  • Do not use the nasal spray in your other nostril unless your doctor has told you to.

  • Do not blow your nose for at least a few minutes after using the nasal spray.

  • If the spray gets in your eyes or mouth or on your skin, rinse with water.

Rinse the tip of the spray bottle with warm water before and after each use.

Do not use a nafarelin nasal spray bottle for longer than 30 days, even if it still contains some medicine. After 30 days of regular use, the amount of medicine left in the bottle will not be enough for you to receive a full dose. If your doctor increases your dose, you may need to get a new bottle to be sure you have enough medicine for full doses.

Read all patient information, medication guides, and instruction sheets provided to you. Ask your doctor or pharmacist if you have any questions.

When you first start using nafarelin nasal to treat precocious puberty, you may notice an increase in signs of puberty, such as enlarged breasts or vaginal bleeding. These are normal side effects during the first month of use.

Call your doctor if pubertal signs continue for longer than 1 month.

Use nafarelin nasal regularly to get the most benefit. Get your prescription refilled before you run out of medicine completely.

To be sure this medicine is helping your condition and is not causing harmful effects, your doctor will need to check your progress on a regular basis.

Store nafarelin nasal in an upright position at room temperature, away from moisture, heat, and light. Do not freeze. Keep the bottle tightly capped when not in use.

What happens if I miss a dose?

Use the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not use extra medicine to make up the missed dose.

It is very important that you DO NOT MISS A DOSE of this medicine.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking Synarel (nafarelin nasal)?

Try not to sneeze or blow your nose just after using the spray. This may decrease the amount of nafarelin your body absorbs.

Avoid using any other nasal sprays within 2 hours after your dose of nafarelin nasal. If you have a stuffy nose, ask your doctor before using a decongestant nasal spray.

Synarel (nafarelin nasal) side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have:

  • heavy or continued menstrual bleeding;

  • pelvic pain or swelling;

  • a seizure (convulsions); or

  • signs of a pituitary gland problem--sudden headache, confusion, vision changes, vomiting, weak pulse, slowed breathing.

Some side effects can be expected during the first month of using nafarelin nasal and are not a reason to stop using the medicine. Tell your doctor if you have any side effect that is bothersome.

Common side effects may include:

  • light vaginal bleeding or spotting;

  • decreased menstrual flow (your periods may stop during treatment);

  • changes in breast size;

  • oily skin or acne, increased body odor;

  • increase in pubic hair growth;

  • headache;

  • hot flashes;

  • mood changes;

  • vaginal dryness; or

  • changes in sexual desire.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

See also: Side effects (in more detail)

What other drugs will affect Synarel (nafarelin nasal)?

Other drugs may interact with nafarelin nasal, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.

Where can I get more information?

  • Your pharmacist can provide more information about nafarelin nasal.
  • Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.
  • Disclaimer: Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Copyright 1996-2012 Cerner Multum, Inc. Version: 5.01.

Date modified: October 14, 2016
Last reviewed: January 15, 2016