Description and Brand Names

Drug information provided by: Merative, Micromedex®

US Brand Name

  1. Synarel

Descriptions


Nafarelin nasal spray is a synthetic (man-made) hormone that is similar to a natural hormone that is produced in the brain. It is used for the treatment of:

  • Central precocious puberty (CPP), a condition which causes early puberty in boys (before 9 years of age) and in girls (before 8 years of age), or
  • Endometriosis, a painful condition caused by extra tissue growing inside or outside of the uterus (womb).

When given regularly to boys and girls experiencing early puberty, nafarelin slows down the development of genital areas in both sexes. It will also slow breast development in girls. This medicine will delay puberty as long as the child continues to use it.

When given regularly to women, nafarelin decreases estrogen levels which helps treat endometriosis. It prevents the growth of tissue caused by endometriosis in adult women during treatment and for 6 months after treatment is discontinued.

Suppressing estrogen can cause thinning of the bones or slowing of growth. This is a problem for adult women whose bones are no longer growing. Slowing the growth of bones is a positive effect for girls and boys whose bones grow too fast when puberty begins too early. Boys and girls may benefit by adding inches to their adult height when nafarelin causes their bones to grow at the proper and expected rate for children.

This medicine is available only with your doctor's prescription.

This product is available in the following dosage forms:

  • Spray

Before Using

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:

Allergies

Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Pediatric

Appropriate studies performed to date have not demonstrated pediatric-specific problems that would limit the usefulness of nafarelin nasal spray in children. Nafarelin will stop having an effect on a child treated for central precocious puberty soon after the child stops using it, and puberty will advance normally.

Appropriate studies have not been performed on the relationship of age to the effects of nafarelin nasal spray for the treatment of endometriosis in the pediatric population. Safety and efficacy have not been established.

Geriatric

No information is available on the relationship of age to the effects of nafarelin nasal spray in geriatric patients.

Breastfeeding

Studies in women breastfeeding have demonstrated harmful infant effects. An alternative to this medication should be prescribed or you should stop breastfeeding while using this medicine.

Drug Interactions

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.

  • Bepridil
  • Cisapride
  • Dronedarone
  • Levoketoconazole
  • Mesoridazine
  • Pimozide
  • Piperaquine
  • Saquinavir
  • Sparfloxacin
  • Terfenadine
  • Thioridazine
  • Ziprasidone

Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

  • Adagrasib
  • Alfuzosin
  • Amiodarone
  • Amisulpride
  • Amitriptyline
  • Anagrelide
  • Apomorphine
  • Aripiprazole
  • Aripiprazole Lauroxil
  • Arsenic Trioxide
  • Asenapine
  • Astemizole
  • Atazanavir
  • Azithromycin
  • Bedaquiline
  • Buprenorphine
  • Ceritinib
  • Chloroquine
  • Chlorpromazine
  • Ciprofloxacin
  • Citalopram
  • Clarithromycin
  • Clofazimine
  • Clomipramine
  • Clothiapine
  • Clozapine
  • Crizotinib
  • Cyclobenzaprine
  • Dabrafenib
  • Dasatinib
  • Delamanid
  • Desipramine
  • Deutetrabenazine
  • Dexmedetomidine
  • Disopyramide
  • Dofetilide
  • Dolasetron
  • Domperidone
  • Donepezil
  • Doxepin
  • Droperidol
  • Ebastine
  • Efavirenz
  • Encorafenib
  • Entrectinib
  • Eribulin
  • Erythromycin
  • Escitalopram
  • Etrasimod
  • Famotidine
  • Felbamate
  • Fexinidazole
  • Fingolimod
  • Flecainide
  • Fluconazole
  • Fluoxetine
  • Formoterol
  • Foscarnet
  • Fosphenytoin
  • Fostemsavir
  • Galantamine
  • Gatifloxacin
  • Gemifloxacin
  • Gepirone
  • Glasdegib
  • Granisetron
  • Halofantrine
  • Haloperidol
  • Hydroquinidine
  • Hydroxychloroquine
  • Hydroxyzine
  • Ibutilide
  • Iloperidone
  • Imipramine
  • Inotuzumab Ozogamicin
  • Itraconazole
  • Ivabradine
  • Ivosidenib
  • Ketoconazole
  • Lapatinib
  • Lefamulin
  • Lenvatinib
  • Leuprolide
  • Levofloxacin
  • Lofexidine
  • Lumefantrine
  • Macimorelin
  • Mefloquine
  • Methadone
  • Metronidazole
  • Mifepristone
  • Mirtazapine
  • Mizolastine
  • Mobocertinib
  • Moxifloxacin
  • Nelfinavir
  • Nilotinib
  • Norfloxacin
  • Octreotide
  • Ofloxacin
  • Olanzapine
  • Ondansetron
  • Osilodrostat
  • Osimertinib
  • Oxaliplatin
  • Ozanimod
  • Pacritinib
  • Paliperidone
  • Panobinostat
  • Paroxetine
  • Pasireotide
  • Pazopanib
  • Pentamidine
  • Perphenazine
  • Phenobarbital
  • Pimavanserin
  • Pipamperone
  • Pitolisant
  • Ponesimod
  • Posaconazole
  • Primidone
  • Probucol
  • Procainamide
  • Prochlorperazine
  • Promethazine
  • Propafenone
  • Protriptyline
  • Quetiapine
  • Quinidine
  • Quinine
  • Quizartinib
  • Ranolazine
  • Relugolix
  • Ribociclib
  • Rilpivirine
  • Risperidone
  • Ritonavir
  • Selpercatinib
  • Sertindole
  • Sertraline
  • Sevoflurane
  • Siponimod
  • Sodium Phosphate
  • Sodium Phosphate, Dibasic
  • Sodium Phosphate, Monobasic
  • Solifenacin
  • Sorafenib
  • Sotalol
  • Sulpiride
  • Sunitinib
  • Tacrolimus
  • Tamoxifen
  • Telaprevir
  • Telavancin
  • Telithromycin
  • Tetrabenazine
  • Tolterodine
  • Toremifene
  • Trazodone
  • Triclabendazole
  • Trimipramine
  • Vandetanib
  • Vardenafil
  • Vemurafenib
  • Venlafaxine
  • Vilanterol
  • Vinflunine
  • Voclosporin
  • Voriconazole
  • Vorinostat
  • Zuclopenthixol

Other Interactions

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Other Medical Problems

The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:

  • Abnormal or unusual vaginal bleeding—Should not be used in patients with this condition.
  • Alcohol abuse or
  • Cigarette smoking or
  • Conditions that increase the chances of developing thinning bones or
  • Osteoporosis (brittle bones), or history of—Increases your risk of developing osteoporosis.
  • Brain tumors, history of or
  • Seizures or epilepsy, history of or—Use with caution. May increase risk for seizures.
  • Depression, history of or
  • Mental problems, history of or
  • Polycystic ovarian disease (PCOD) or
  • Pituitary gland problem or
  • Rhinitis (swelling or irritation of the nose)—Use with caution. May make these conditions worse.

Proper Use

Use this medicine only as directed by your doctor. Do not use more of it, do not use it more often, and do not use it for a longer time than your doctor ordered. Do not change your dose or stop using this medicine without checking first with your doctor.

This medicine comes with patient instructions. Read and follow these instructions carefully and make sure you understand:

  • How to prepare the nasal spray.
  • How to use the spray.
  • How long the spray can be stored.

This medicine is only used in the nose. Do not get it in your eyes or on your skin. If it does get on these areas, rinse them with water right away and call your doctor.

To use nafarelin spray:

  • Before you use each new bottle of nafarelin, the spray pump needs to be primed first. To do this, point the bottle away from you and pump the bottle firmly about 7 times until a fine mist spray appears. This only needs to be done once for each new bottle of nafarelin. Be careful not to breathe in this spray. You could inhale extra doses of nafarelin, since the medicine is dissolved in the spray.
  • Before you use nafarelin spray, blow your or your child's nose gently to clear the nostrils. You can also use a bulb syringe to clean your child's nose.
  • For central precocious puberty:
    • Tilt your child's head back slightly. Put the tip of the bottle into your child's nostril.
    • Close the other nostril with your finger. At the same time, let your child sniff in the spray as you pump the bottle once.
    • Allow 30 seconds between sprays in the same nostril.
    • Keep your child's head tilted back for a few seconds after spraying this medicine to let the spray get onto the back of the nose.
  • For endometriosis:
    • Lean your head forward. Put the spray tip into one nostril. Aim the tip toward the back and outside of your nostril. You do not need to put the tip too far into your nose.
    • Close your other nostril with your finger. At the same time, sniff in the spray as you pump the bottle once.
    • Do not spray this medicine in your other nostril unless your doctor tells you to.
    • Tilt your head backwards for a few seconds after spraying this medicine to let the spray get onto the back of your nose.
  • Repeat these steps for each dose of the medicine.
  • Each time you use the spray bottle, wipe off the tip with a clean tissue or cloth. Keep the white safety clip and plastic cap on the bottle when you are not using it.
  • Be sure to clean the tip of the spray bottle before and after every use. To do this, hold the bottle sideways. Rinse the tip with warm water, while wiping the tip with your finger or a soft cloth for about 15 seconds. Dry the tip with a soft cloth or tissue. Replace the cap right after use. Be careful not to get water into the bottle, since this could dilute the medicine.
  • Do not try to make the tiny hole in the spray tip larger. Doing so, may deliver a wrong dose of the medicine.

If you are also using a nasal decongestant, do not use it at the same time you are using this medicine. Wait at least 2 hours after using nafarelin spray before using the nasal decongestant.

Avoid sneezing when spraying and immediately after using the medicine. If you sneeze, the medicine may not be absorbed as well.

Many boys and girls who have central precocious puberty will not feel sick or will not understand the importance of taking this medicine regularly. Nafarelin must be given on a regular schedule.

Women with endometriosis should start using this medicine between the 2nd and 4th day of their menstrual period, unless instructed otherwise by your doctor. This medicine is used for six months.

Dosing

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For nasal dosage form (spray):
    • For treatment of central precocious puberty:
      • Children—Two sprays in each nostril 2 times a day, in the morning and in the evening. This provides a total dose of 8 sprays a day. Some patients may need a larger dose by using 3 sprays in alternating nostrils 3 times a day to provide a total of 9 sprays per day.
    • For treatment of endometriosis:
      • Adults—One spray into one nostril in the morning and one spray into the other nostril in the evening, taken for 6 months. Start your treatment between Days 2 and 4 of your menstrual period.
      • Children—Use and dose must be determined by your doctor.

Missed Dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep the bottle upright. Do not freeze. After you prime the bottle, there will only be 60 doses or sprays. Keep track of the number of sprays you use. Throw the bottle away after you use 60 sprays (for 30 days) even if some liquid remains.

Precautions

It is very important that your doctor check the progress of you or your child at regular visits to make sure that this medicine is working properly. Blood tests may be needed to check for unwanted effects. Be sure to keep all appointments.

For female patients: You should not use this medicine if you are pregnant or may become pregnant. Using this medicine while you are pregnant can harm your unborn baby. Use an effective form of birth control to keep from getting pregnant during treatment with this medicine. If you think you have become pregnant while using the medicine, tell your doctor right away.

For children using nafarelin spray for central precocious puberty (CPP): This medicine can cause a brief increase in blood levels of some hormones. During this time, you may notice more signs of puberty in your child, including light vaginal bleeding and breast enlargement in girls. If your child's symptoms do not improve within 4 weeks, or if they get worse, call your doctor.

For adult women using nafarelin spray for endometriosis:

  • For the first few days of treatment, the symptoms of your condition may get worse. This is normal. Do not stop using this medicine. Talk with your doctor if you have concerns about this.
  • During the time you are using nafarelin, your menstrual period may not be regular or you may not have a menstrual period at all. This is to be expected when being treated with this medicine. If regular menstruation does not begin within 2 to 3 months after you stop using this medicine, check with your doctor.
  • During the time you are using nafarelin spray, you should use birth control methods that do not contain hormones, such as condoms, IUD, a diaphragm or a cervical cap with a spermicide. If you have any questions about this, check with your doctor.
  • Use a water-based vaginal lubricant product if dryness of the vagina causes problems, such as pain during sexual intercourse. Make sure the lubricant you choose can be used with a latex birth control device if you are using one. Some lubricants contain oils, which can break down the latex rubber of condoms, a cervical cap, or a diaphragm, and cause them to rip or tear.
  • This medicine can cause your bone mineral density to decrease, which may lead to osteoporosis or weakened bones. Talk with your doctor about how this risk will affect you.
  • If you suspect you may have become pregnant, stop using this medicine and check with your doctor right away. There is a chance that continued use of nafarelin during pregnancy could cause birth defects or a miscarriage.

This medicine may cause depression especially in women. Check with your doctor right away if you have discouragement, feeling sad or empty, irritability, lack of appetite, loss of interest or pleasure, tiredness, trouble concentrating, or trouble sleeping.

This medicine may cause some people to be agitated, irritable, or display other abnormal behaviors. Make sure the doctor knows if you have trouble sleeping, get upset easily, have a big increase in energy, or start to act reckless. Also tell the doctor if you have sudden or strong feelings, such as feeling nervous, angry, restless, violent, or scared. If you or your caregiver notice any of these side effects, tell your doctor right away.

Using this medicine may increase your risk of having seizures. Check with your doctor right away if you start to have muscle spasm or jerking of all extremities, seizures, sudden loss of consciousness, or loss of bladder control.

Nafarelin spray can increase your risk of having cysts in the ovaries. Talk to your doctor about this risk.

This medicine may cause intracranial hypertension or pseudotumor cerebri (increased pressure in the head) in children. Check with your doctor right away if your child have blurred or double vision, change in ability to see colors, especially blue or yellow, continuing ringing or buzzing or other unexplained noise in the ears, dizziness, eye pain, hearing loss, nausea and vomiting, or severe headache.

Before you have any medical tests, tell the medical doctor in charge that you are using this medicine. The results of some tests may be affected by this medicine.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

Side Effects

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

More common

For adults (female)
  1. Breast enlargement
  2. light vaginal bleeding between regular menstrual periods, called spotting
  3. longer or heavier menstrual periods
  4. vaginal bleeding between regular menstrual periods, called breakthrough bleeding
For children (male)
  1. Body odor
  2. growth of pubic hair
For children (female)
  1. Body odor
  2. breast enlargement
  3. growth of pubic hair
  4. light vaginal bleeding between regular menstrual periods, called spotting
  5. longer or heavier menstrual periods
  6. vaginal bleeding between regular menstrual periods, called breakthrough bleeding

Less common

  1. Chest pain
  2. rash, hives or welts, itching
  3. redness of the skin

Less common or rare

For adults (female)
  1. Fast or irregular heartbeat
  2. numbness or tingling of the hands or feet
  3. pain in the eyes or joints
  4. patchy brown or dark brown discoloration of the skin
  5. pelvic bloating or tenderness
  6. unexpected or excess milk flow from the breasts
  7. unusual tiredness or weakness

Incidence not known

For adults (female)
  1. Cough
  2. difficulty with speaking
  3. dizziness or lightheadedness
  4. double vision
  5. fainting
  6. fast heartbeat
  7. inability to move the arms, legs, or facial muscles
  8. inability to speak
  9. nausea
  10. pain or discomfort in the arms, jaw, back, or neck
  11. pain, redness, or swelling in the arm or leg
  12. slow speech
  13. sweating
  14. trouble breathing
  15. vomiting
  16. yellow eyes or skin

Incidence not known

  1. Anxiety or mental depression
  2. blurred or double vision
  3. change in ability to see colors, especially blue or yellow
  4. changes in vision
  5. cold, clammy, or pale skin
  6. confusion
  7. discouragement
  8. eye pain
  9. feeling sad or empty
  10. headache
  11. irregular heartbeats
  12. irritability
  13. lack of appetite
  14. loss of interest or pleasure
  15. nightmares or unusually vivid dreams
  16. seizures
  17. slow heart rate
  18. trouble concentrating
  19. trouble sleeping
  20. vomiting
  21. weakness

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

For adults (female)
  1. Acne
  2. dandruff
  3. hot flashes
  4. increase or decrease in sexual desire
  5. increased hair growth, often abnormally distributed
  6. mood swings
  7. muscle pain
  8. oily skin
  9. pain during sexual intercourse
  10. rapid weight gain
  11. reduced breast size
  12. stopping of menstrual periods
  13. swelling of the feet or lower legs
  14. vaginal dryness
For children (male)
  1. Acne
  2. dandruff
  3. mood swings
  4. oily skin
For children (female)
  1. Acne
  2. dandruff
  3. hot flashes
  4. mood swings
  5. oily skin

Less common or rare

For adults (female)
  1. Breast pain
  2. headache (mild and transient)
  3. irritated or runny nose
  4. mental depression (mild and transient)
For children (male)
  1. Irritated or runny nose
For children (female)
  1. Irritated or runny nose
  2. white or brownish vaginal discharge

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.