Synarel (nafarelin) nasal spray is sometimes used in gender-affirming care, particularly as part of puberty suppression therapy for transgender youth experiencing gender dysphoria. It is a gonadotropin-releasing hormone (GnRH) agonist that works by suppressing the production of gonadal hormones, such as estrogen or testosterone, depending on the individual’s assigned sex at birth. While it can be effective in delaying puberty and alleviating gender dysphoria, it’s important to be aware of potential unwanted/adverse/side effects. Here are some of them:
| Side Effect | Description |
| Nasal irritation | Irritation or discomfort in the nasal passages is a common side effect of Synarel nasal spray. This can include symptoms such as nasal congestion, runny nose, sneezing, or nosebleeds. |
| Hot flashes | Synarel can cause hot flashes or flushing, which are sudden feelings of warmth, sweating, and redness of the face and body. These symptoms are more common during the initial period of treatment and usually improve over time. |
| Headaches | Headaches are a common side effect of Synarel use, though they are usually mild and temporary. If headaches become severe or persistent, medical attention may be needed. |
| Mood changes | Some individuals may experience mood swings, irritability, or changes in emotional well-being while taking Synarel. |
| Decreased bone density | Long-term use of Synarel may lead to decreased bone density (osteopenia or osteoporosis) due to the suppression of gonadal hormones. Bone density monitoring and supplementation with calcium and vitamin D may be recommended to mitigate this risk. |
| Decreased libido | A decrease in libido (sex drive) can occur as a side effect of Synarel treatment due to the suppression of gonadal hormones. |
| Fatigue | Fatigue or feelings of lethargy may occur as a side effect of Synarel treatment, particularly during the initial period of adjustment. |
| Breast tenderness and enlargement | In individuals assigned male at birth, Synarel may cause breast tenderness and enlargement due to the suppression of testosterone and promotion of estrogenic effects. |
| Vaginal dryness or discomfort | In individuals assigned female at birth, Synarel may cause vaginal dryness or discomfort due to the suppression of estrogen. |
| Thinning of hair | Some individuals may experience hair thinning or loss (alopecia) as a side effect of Synarel treatment, though this is less common. |
| Delayed growth | In transgender youth undergoing puberty suppression therapy, Synarel may delay growth and development of secondary sexual characteristics associated with puberty. |
| Rare allergic reactions | Although rare, some individuals may experience allergic reactions to Synarel, including rash, itching, swelling, or difficulty breathing. Immediate medical attention is necessary if any signs of an allergic reaction occur. |
https://www.healthlinkbc.ca/medications/nafarelin-acetate-spray-nasal