We present the case of a young adult female who presented to the emergency department with headache and vomiting. After treatment with intravenous fluids, diphenhydramine and metoclopramide the headache completely resolved. Because of the patient's persistent symptoms and past medical history of systemic lupus erythematosus, a noncontrast head CT scan was done. In this case, the patient had a subarachnoid hemorrhage with edema and mass effect, detected on a noncontrast head CT scan. The patient required a nicardipine drip for blood pressure control. The patient recovered well and was discharged at her normal state of health. This case demonstrates the importance of maintaining high clinical suspicion for life-threatening emergencies even in patients with unremarkable physical exams who experience symptomatic improvement after treatment.