Mast cell activation syndrome (MCAS) is a relatively new diagnosis for a constellation of symptoms with sometimes devastating results for patients. A 40-year old woman with MCAS underwent arthroscopic repair of her right shoulder, with successful anesthetic management. This case report discusses the basic immunologic physiology surrounding this syndrome, myriad medications often used by this patient population, and the anesthetic management of this patient. With additional knowledge of this disorder, exposure to its clinical presentation in the perioperative setting, and anesthetic considerations specific to MCAS, the Certified Registered Nurse Anesthetist will be better equipped to effectively manage the complex requirements of this patient population.