Precocious puberty, if treated promptly for the primary cause, is generally free of side effects. In case of idiopathic precocious puberty without a cause, it is currently treated with gonadotropin-releasing hormone analogue injection (abbreviated as GnRHa in English). With this injection treatment, early symptoms such as mild dizziness, rash and hypothermia can occur, but appropriate adjustment of the drug dose can be relieved and does not affect the continuation of treatment. In addition, during the first week of injection, some patients may experience transient vaginal bleeding, i.e., the ignition effect, which does not require treatment and can disappear naturally after continued treatment.