Systemic Mastocytosis (SM) is a hematologic neoplasm characterized by an abnormal proliferation of mast cells, which have the potential to infiltrate one or more visceral organs. Patients can present with a wide constellation of symptoms making it a challenging diagnosis for clinicians. Non-specific symptoms such as fatigue, headache, and weight loss may predominate; however, some patients may present with acute onset of urticaria, flushing, and diarrhea. Due to its rarity, clinicians often face a challenge in evaluating, diagnosing and effectively treating systemic mastocytosis. Identification during the indolent phase is important as SM can progress to aggressive leukemias or myeloproliferative disorders. In this article, we present a case of SM, and discuss current practices in diagnosis, evaluation and management. We conclude with future directions for treatments and diagnosis