An 8-year-old girl with idiopathic central precocious puberty experienced multiple episodes of anaphylaxis after receiving a goserelin acetate implant. She was hospitalized and treated with epinephrine, antihistamine, and corticosteroids. The goserelin implant was surgically excised; however, anaphylactic symptoms continued for 4 days after excision. Less severe systemic symptoms recurred 6 weeks after removal; these were possibly due to leakage of the depot drug into subcutaneous tissues. It was noted that 3 years earlier, the patient had developed a similar, milder systemic allergic reaction to leuprolide acetate that required treatment with oral prednisone and antihistamines. Intradermal testing yielded positive results for leuprolide. Gonadotropin-releasing hormone (GnRH) analogs, including leuprolide acetate and goserelin acetate, are commonly prescribed for patients with prostatic carcinoma, endometriosis, and precocious puberty. A literature review identified a single case report of a systemic hypersensitivity reaction involving goserelin acetate and several reports of systemic hypersensitivity reactions associated with leuprolide acetate. We found no reports of systemic reactions to GnRH analogs in pediatric patients. Clinicians should be aware of the potential association of GnRH analogs with systemic reactions. They should also recognize that recurrent anaphylaxis may occur due to the long half-life of these therapeutic agents in tissue.