What is Nafarelin?

Nafarelin is a hormone medication mainly used to help stop the growth of tissue, pain during intercourse, and menstrual cramps that are associated with endometriosis. The hormone found in this medication is similar to what is naturally created by the body and released by the hypothalamus gland. This medication works by suppressing the release of certain hormones in the body, which causes a menopause-like state, and shrinks the lining of the uterus. It is also used to halt early puberty in young children.

The luteinizing hormone (LH) and follicle-stimulating hormones (FSH) are known as gonadotropins. Gonadotropins are an important part of regulating reproductive function and sexual development. Gonadotropin-releasing hormone (GnRH) regulates the output of gonadotropins by the pituitary gland. Nafarelin is a GnRH agonist — a chemical that combines with the receptor of a cell to trigger a physiological response — which is thought to cease production of estrogen. In women with endometriosis, this means that endometrial growths will be deprived of estrogen, which will cause them to become inactive and eventually deteriorate.

In addition to treating endometriosis, nafarelin is sometimes used to stop central precocious puberty (CPP) in young children. This medication is given to both female and male patients to help slow down or halt the process of early puberty by preventing the growth of breast tissue, genital development, and growth of excess body hair and bone tissue. Though nafarelin begins working immediately, the effects on sexual development may take several months to become noticeable, and will stop altogether shortly after use is discontinued.

Nafarelin is usually prescribed in the form of a nasal spray. Adult women are generally advised to take 0.2 milligrams a day. These doses are given in a single spray, two times a day in alternating nostrils. For children, this medication is generally given in 0.8-milligram sprays, two sprays in each nostril, two times per day.

As with most other medications, nafarelin is not without potential side effects. Most side effects are considered temporary and mild, and may include changes in vaginal secretion or unusual bleeding, acne or oily skin, and mood swings. More severe side effects can include chest pain, shortness of breath, or stomach pain. In adult women, this medication can also lead to bone thinning, which is why many women will only be prescribed this medication for a maximum of six months.