Other drug names:	A-Am  An-Az  B  C-Ch  Ci-Cz  D-Dh  Di-Dz  E  F  G  H  I-J  K-L  M-Mh  Mi-Mz  N-Nh  Ni-Nz  O  P-Pl  Pm-Pz  Q-R  S-Sn  So-Sz  T-To  Tp-Tz  U-V  W-Z  0-9

In the U.S.—

Synarel

In Canada—

Synarel

• Antiendometriotic agent
• gonadotropin inhibitor
• gonadotropin-releasing hormone analog

Nafarelin (NAF-a-re-lin ) is a hormone similar to the one normally released from the hypothalamus gland in the brain. It is used in the treatment of:

• Endometriosis, a painful condition caused by extra tissue similar to the lining of the uterus growing inside and outside of the uterus.
• Central precocious puberty (CPP), puberty developing too early in boys and girls.

Nafarelin works by decreasing the amount of estrogen and testosterone in the blood.

When given regularly to boys and girls, this medicine helps to prevent them from continuing to develop the sexual features associated with puberty, slowing down the development of breasts in girls and the development of genital areas in boys and girls. This medicine delays puberty in a child only as long as the child continues to take it.

Nafarelin prevents the growth of tissue associated with endometriosis in adult women during treatment and for 6 months after treatment is discontinued. Reducing the amount of estrogen in the body is one way of treating endometriosis.

Suppressing estrogen can thin the bones or slow their growth. This is a problem for adult women whose bones are no longer growing like the bones of children. Slowing the growth of bones is a positive effect for girls and boys whose bones grow too fast when puberty begins too early. This is why nafarelin is used only for up to 6 months in adult women treated for endometriosis, but often is used for a longer time in girls and boys with pubertal problems. Boys and girls may benefit by adding inches to their adult height when nafarelin causes their bones to grow at a proper rate.

Nafarelin is available only with your doctor's prescription, in the following dosage form:

Nasal
• Solution (U.S. and Canada)

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 nafarelin, the following should be considered:

Allergies—Tell your doctor if you have ever had any unusual or allergic reaction to nafarelin or to gonadotropin-releasing hormone–like medicines. Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes.

Pregnancy—Nafarelin use is not recommended during pregnancy. Nafarelin has not been studied in pregnant women. It has been shown to cause problems in animals, such as low birth weights and a slight decrease in the number of successful pregnancies.

For treatment of endometriosis— Stop taking this medicine immediately and check with your doctor if you suspect that you may have become pregnant.

Breast-feeding—It is not known whether nafarelin passes into the breast milk. However, use of nafarelin is not recommended during breast-feeding because it may cause unwanted effects in nursing babies.

Children—Studies of this medicine for treatment of endometriosis have been done only in adult patients, and there is no specific information comparing use of nafarelin to treat this condition in children younger than 18 years of age with use in other age groups. Endometriosis is not likely to occur before puberty.

When used to treat a child for central precocious puberty, nafarelin will stop having an effect soon after the child stops using it, and puberty will advance normally. It is not known if nafarelin causes:

• Changes in boys' and girls' future abilities to have babies after having used nafarelin around the time of puberty. Their chances of having children later are thought to be normal.
• Problems in the ovaries, such as cysts or a larger than normal ovary. Nafarelin stimulates the ovaries in adult women and has caused these problems in the ovary. It is not known whether nafarelin can also have these effects in younger girls treated for central precocious puberty.

It is especially important that you discuss with the child's doctor the good that this medicine may do as well as the risks of using it.

Other medicines—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 nafarelin, it is especially important that your health care professional know if you are taking the following:

• Nasal decongestant sprays—It is not known whether nasal decongestant sprays can decrease the amount of nafarelin that enters the bloodstream through the lining of the nose. For this reason, you should wait at least 2 hours after using nafarelin before you use a nasal decongestant spray

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

• Bleeding from the vagina (abnormal or of unknown cause)—For adult women treated for endometriosis or girls treated for central precocious puberty, using nafarelin when the reason for vaginal bleeding is not known may make it harder for the doctor to find the cause of the problem, and may cause a delay in treatment of the condition
• Other conditions that increase the chances of developing thinning bones or osteoporosis (brittle bones)—If you are an adult female being treated for endometriosis, it is important that your doctor know if you already have an increased risk of osteoporosis. Some things that can increase your risk for having osteoporosis include cigarette smoking, alcohol abuse, and a family history of osteoporosis or easily broken bones. Some medicines, such as corticosteroids (cortisone-like medicines) or anticonvulsants (seizure medicine), can also cause thinning of the bones when used for a long time

You will be given a fact sheet with your prescription for nafarelin that explains how to use the pump spray bottle. If you have any questions about using the pump spray, ask your health care professional.

To use nafarelin spray:

• Before you use each new bottle of nafarelin, the spray pump needs to be started. To do this, point the bottle away from you and pump the bottle firmly about seven times. A spray should come out by the seventh time you pump the spray bottle. 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 take your daily doses of nafarelin, blow your nose gently. Hold your head forward a little. 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 off by pressing on the outside of your nose with a finger. Then, sniff in the spray as you pump the bottle once.
• Take the spray bottle out of your nose. Tilt your head back for 30 seconds, to let the spray get onto the back of your nose.
• Repeat these steps for each dose of medicine.
• Each time you use the spray bottle, wipe off the tip with a clean tissue or cloth. Keep the blue safety clip and plastic cap on the bottle when you are not using it.
• Every 3 or 4 days you should clean the tip of the spray bottle. 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.

It is important to avoid sneezing when spraying and immediately after using the medicine. If you sneeze, the medicine may not be absorbed as well.

Use this medicine only as directed by your doctor. Do not use more or less of it, and do not use it more often than your doctor ordered. The exact amount of medicine you need has been carefully worked out. Using too much may increase the chance of side effects, while using too little may not improve your condition.

Many boys and girls who have central precocious puberty will not feel sick or will not understand the importance of taking the medicine regularly. It is very important that the medicine is used exactly as directed and that the proper amount is used at the proper time. It works best when there is a constant amount in the blood. To help keep the amount constant, nafarelin must be given on a regular schedule.

Dosing—

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

• For nasal solution dosage form:
  • For treating central precocious puberty:
    • Children—800 micrograms (mcg) (two sprays into each nostril) two times a day, once in the morning and once in the evening. This provides a total daily dose of eight sprays or 1600 mcg a day. Sometimes a larger dose may be needed. 1800 mcg a day is provided by using three sprays in alternating nostrils three times a day to provide a total of nine sprays a day.
  • For treating endometriosis:
    • Adults—200 mcg (one spray) inhaled into one nostril in the morning and one spray inhaled into the other nostril in the evening, for six months. Begin your treatment on Day 2, 3, or 4 of your menstrual period.

Missed dose—

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

Storage—

To store this medicine:

• Keep out of the reach of children.
• The bottle should be stored standing upright, with the tip up.
• Store away from heat and direct light.
• Keep the medicine from freezing. Do not refrigerate.
• Do not keep outdated medicine or medicine no longer needed. Be sure that any discarded medicine is out of the reach of children.

All scheduled visits to the doctor should be kept, even if the medicine seems to be working properly and you feel well. This is especially important for children using the medicine for treatment of central precocious puberty, even if their condition improves. Their progress still must be checked by the doctor when they are no longer using the medicine.

For children treated for central precocious puberty— Tell the doctor if nafarelin does not stop puberty from progressing within 6 to 8 weeks. You may notice puberty progressing in your child for the first few weeks of therapy, but you should see signs that puberty is stopping within 4 weeks after your child begins nafarelin therapy.

For adult women treated for endometriosis—

• During the time you are receiving 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 menstrual periods do not begin within 2 to 3 months after you stop using this medicine, check with your health care professional.
• To prevent pregnancy if you are sexually active during the time you are using nafarelin, you should use birth control methods that do not contain hormones, such as condoms or a diaphragm or a cervical cap with a spermicide. If you have any questions about this, check with your health care professional.
• 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.
• If you suspect you are pregnant, stop using this medicine and check with your doctor immediately. There is a chance that nafarelin could cause problems to the unborn baby if taken during a pregnancy.

In the first few weeks of therapy, you may notice puberty progressing in your child, including vaginal bleeding and breast enlargement in girls. Within 4 weeks after nafarelin has had time to begin working properly, you should see signs in boys and girls that puberty is stopping. However, pubic hair may continue to show or grow in either boys or girls.

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 as soon as possible if any of the following side effects occur:

• More common
  • For adults (female)
    • Breast enlargement;  light vaginal bleeding between regular menstrual periods called spotting;  longer or heavier menstrual periods;  vaginal bleeding between regular menstrual periods called breakthrough bleeding 
    
    
  • For children (male)
    • Body odor;  growth of pubic hair 
    
    
  • For children (female)
    • Body odor;  breast enlargement;  growth of pubic hair;  light vaginal bleeding between regular menstrual periods called spotting;  longer or heavier menstrual periods;  vaginal bleeding between regular menstrual periods called breakthrough bleeding 
    
    

• Less common or rare
  • For adults (female)
    • Allergic reaction (shortness of breath, chest pain, hives);  fast or irregular heartbeat;  numbness or tingling of hands or feet;  pain in eyes or joints ;  patchy brown or dark brown discoloration of skin ;  pelvic bloating or tenderness;  unexpected or excess milk flow from breasts;  unusual tiredness or weakness 
    
    
  • For children (male and female)
    • Allergic reaction (shortness of breath, chest pain, hives) 
    
    

Other side effects may occur that usually do not need medical attention. Some of these side effects may go away during treatment as your body adjusts to the medicine. However, check with your doctor if any of the following side effects continue or are bothersome:

• More common
  • For adults (female)
    • Acne;  dandruff;  hot flashes;  increase or decrease in sexual desire ;  increased hair growth, often abnormally distributed ;  mood swings;  muscle pain ;  oily skin;  pain during sexual intercourse;  rapid weight gain;  reduced breast size;  stopping of menstrual periods;  swelling of feet or lower legs;  vaginal dryness 
    
    
  • For children (male)
    • Acne;  dandruff;  mood swings;  oily skin 
    
    
  • For children (female)
    • Acne;  dandruff;  hot flashes;  mood swings;  oily skin 
    
    

• Less common or rare
  • For adults (female)
    • Breast pain;  headache (mild and transient) ;  irritated or runny nose;  mental depression (mild and transient);  skin rash  
    
    
  • For children (male)
    • Irritated or runny nose 
    
    
  • For children (female)
    • Irritated or runny nose;  white or brownish vaginal discharge 
    
    

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

Revised: 05/27/1998