Diabetic ketoacidosis (DKA) is a serious disease entity that must be diagnosed quickly for urgent management in the intensive care unit. Keeping DKA in the differential diagnosis is important, especially in a forward deployed, resource-poor setting. The symptoms and signs of DKA are nonspecific, including fatigue, polydipsia, polyuria, weakness, weight loss, nausea, vomiting, and abdominal pain with tachycardia and tachypnea on exam. The testing capability to evaluate for DKA includes a glucometer, urine dipstick, and basal metabolic panel, all of which can be done in most forward deployed settings. The need for a high index of suspicion for DKA in patients with these symptoms is required due to the lack of life-saving insulin and intensive lab monitoring required. The downstream effects of DKA include diabetic coma and death. We present a case report of a 21-year-old otherwise healthy, active duty, male Marine who presents to the clinic with a chief complaint of 4 days of headache and 1 day of nausea with four episodes of non-bloody, non-bilious emesis along with epigastric abdominal pain. He returned to the clinic 2 days later with evidence of tachycardia and increased work of breathing, at which time there was a concern for a pulmonary embolus. By the time he was transferred to the emergency room, he was in severe DKA. The patient was treated in the intensive care unit and made a full recovery. He was processed for limited duty and medical board upon hospital discharge.