how does this medication work? what will it do for me?

nafarelin belongs to a group of medications known as gonadotropin-releasing hormone (gnrh) analogues. it is used to relieve the symptoms of endometriosis (e.g., pelvic pain, dysmenorrhea [painful menstruation]) and to reduce the size and number of endometriotic lesions (areas of endometrial tissue found outside the uterus).

in endometriosis, endometrial tissue is found outside the uterus in areas such as the ovaries, intestines, or other organs in the pelvis. the symptoms of endometriosis (e.g., severe menstrual cramps, pain during sexual intercourse, low back pain, and painful bowel movements) are affected by the body's hormones, especially estrogen. when the estrogen level in the body is low, endometrial tissue shrinks and endometriosis symptoms lessen. nafarelin works by temporarily reducing the body's production of estrogen (which blocks ovulation and menstruation) and relieving the symptoms of endometriosis.

this medication may be available under multiple brand names and/or in several different forms. any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. as well, some forms of this medication may not be used for all of the conditions discussed here.

your doctor may have suggested this medication for conditions other than those listed in these drug information articles. if you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. do not stop taking this medication without consulting your doctor.

do not give this medication to anyone else, even if they have the same symptoms as you do. it can be harmful for people to take this medication if their doctor has not prescribed it.

what form(s) does this medication come in?

each ml of nasal solution contains nafarelin acetate 2 mg (as nafarelin base). each spray delivers approximately 200 µg nafarelin base. each bottle contains at least 60 sprays. nonmedicinal ingredients: benzalkonium chloride, glacial acetic acid, hydrochloric acid or sodium hydroxide, sorbitol, and purified water.

how should i use this medication?

the usual recommended dose of nafarelin nasal spray is one spray (200 µg) into one nostril in the morning, and one spray into the other nostril in the evening, for a total daily dose of 400 µg. the doses should be approximately 12 hours apart. some women may require higher doses (e.g., 800 µg per day).

treatment should be started between the second and fourth day after the beginning of menstrual bleeding. during the first 2 months of using nafarelin, vaginal bleeding, also known as breakthrough bleeding, may occur. the length of treatment is usually for 6 months, unless otherwise instructed by your doctor.

ask your doctor or pharmacist to teach you the proper way to use this nasal spray. if you are using this medication for the first time or using a new bottle of nafarelin you will need to prime the spray pump. to prime the spray pump, turn the tip of the bottle away from you, put 2 fingers on the "shoulders" of the spray bottle and put your thumb at the bottom of the bottle, and push down 7 to 10 times until you see a fine mist appear.

gently blow your nose to clear your nostrils before each use. if you sneeze during or immediately after the dose, contact your doctor or pharmacist for advice.

after each use, clean the spray tip by holding the bottle in a horizontal position and rinsing the spray tip with warm water while wiping the tip with your finger or a soft cloth for approximately 15 seconds.

if you are using another nasal spray (e.g., a decongestant spray), wait 30 minutes after using nafarelin nasal spray before using the other nasal spray.

many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. if your doctor has recommended a dose different from the ones listed here, do not change the way that you are using the medication without consulting your doctor.

it is important to use this medication exactly as prescribed by the doctor. for this medication to be effective, it must be used regularly without interruption (e.g., no missed doses). if you miss a dose of this medication, contact your doctor or pharmacist for advice. do not take a double dose to make up for a missed one.

store this medication at room temperature in an upright position, protect it from light, and keep it out of the reach of children. do not freeze the medication.

do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. ask your pharmacist how to dispose of medications that are no longer needed or have expired.

who should not take this medication?

do not use this medication if you:

  • are allergic to nafarelin, or any ingredients of the medication
  • are allergic to related medications (i.e., other gnrh analogues)
  • are breast-feeding
  • are pregnant or may become pregnant during treatment
  • have abnormal vaginal bleeding that has not been evaluated by your doctor

what side effects are possible with this medication?

many medications can cause side effects. a side effect is an unwanted response to a medication when it is taken in normal doses. side effects can be mild or severe, temporary or permanent.

the side effects listed below are not experienced by everyone who takes this medication. if you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

the following side effects have been reported by at least 1% of people taking this medication. many of these side effects can be managed, and some may go away on their own over time.

contact your doctor if you experience these side effects and they are severe or bothersome. your pharmacist may be able to advise you on managing side effects:

  • acne
  • appetite changes (increased/decreased)
  • breast pain
  • changes in breast size (enlarged or reduced)
  • changes in taste
  • constipation
  • dandruff
  • change in sexual desire
  • diarrhea
  • dizziness
  • dry nose
  • dry skin
  • excessive sweating
  • feeling of "fullness"
  • hair loss
  • headache
  • hot flashes
  • increased hair growth, often abnormally distributed
  • irritation to tissues inside the nose
  • mood swings
  • muscle pain
  • nausea
  • nervousness
  • runny nose
  • stomach irritation
  • stopping of menstrual periods
  • swelling of the feet or lower legs
  • trouble sleeping
  • vaginal dryness
  • vomiting
  • weakness
  • weight changes (increase or decrease)

although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.

check with your doctor as soon as possible if any of the following side effects occur:

  • ear pain
  • eye pain
  • joint pain
  • nosebleeds
  • pain during or after sexual intercourse
  • palpitations (rapid, pounding heartbeat)
  • red eyes (conjunctivitis)
  • signs of depression (e.g., poor concentration, changes in weight, changes in sleep, decreased interest in activities, thoughts of suicide)
  • skin rash
  • spinning sensation
  • symptoms of ovarian stimulation syndrome (e.g., bloating, abdominal pain, increased weight, nausea, vomiting, diarrhea)
  • vaginal bleeding

stop taking the medication and seek immediate medical attention if any of the following occur:

  • signs of an allergic reaction (shortness of breath or difficulty breathing; hives; swelling of the eyes, mouth, lips, or throat)

some people may experience side effects other than those listed. check with your doctor if you notice any symptom that worries you while you are taking this medication.

are there any other precautions or warnings for this medication?

before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. these factors may affect how you should use this medication.

birth control: even though nafarelin blocks ovulation, it does not provide reliable birth control. women should use a nonhormonal method of birth control (e.g., condoms, diaphragms) while taking this medication. do not use birth control pills while taking this medication.

bone density: over a 6-month course of treatment, this medication may cause a small loss in bone density, some of which may not be reversible. this loss of bone density is usually not significant for healthy people. talk to your doctor about the risks and benefits of using this medication if you have risk factors for low bone density, such as:

  • chronic use of alcohol or tobacco
  • a family history of osteoporosis (thinning of the bones with fractures)
  • use of other medications that can reduce bone mass (such as antiepileptic medications or corticosteroids)

menstrual periods: when nafarelin is used regularly at the recommended doses, menstrual periods will stop. if regular menstrual periods continue, contact your doctor. if you miss one or more of doses of nafarelin, you may experience breakthrough vaginal bleeding.

pregnancy: this medication should not be used during pregnancy. if you become pregnant while taking this medication, stop the medication and contact your doctor immediately.

breast-feeding: it is not known if nafarelin passes into breast milk or if breast-fed babies experience any side effects of nafarelin use by the mother. if you are breast-feeding and are taking this medication, it may affect your baby. it is generally recommended that women using this medication do not breast-feed.

children: the safety and effectiveness of using this medication have not been established for children.

what other drugs could interact with this medication?

there may be an interaction between nafarelin nasal spray and any of the following:

  • birth control pills
  • decongestant nasal sprays
  • other nasal sprays

if you are taking any of these medications, speak with your doctor or pharmacist. depending on your specific circumstances, your doctor may want you to:

  • stop taking one of the medications,
  • change one of the medications to another,
  • change how you are taking one or both of the medications, or
  • leave everything as is.

an interaction between two medications does not always mean that you must stop taking one of them. speak to your doctor about how any drug interactions are being managed or should be managed.

medications other than those listed above may interact with this medication. tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. also tell them about any supplements you take. since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.

all material copyright mediresource inc. 1996 – 2023. terms and conditions of use. the contents herein are for informational purposes only. always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. source: www.medbroadcast.com/drug/getdrug/synarel