Nausea and vomiting are common symptoms most frequently caused by gastrointestinal etiologies. Alternatively, panhypopituitarism is a rare condition in which two or more pituitary hormones are deficient. In this case, we describe a 25-year-old type II diabetic woman with severe and persistent nausea and vomiting. She had lost 9 kg of weight since her symptoms began 5 weeks prior. Vital signs were normal, and laboratory studies showed metabolic acidosis thought to be due to fasting ketosis. She underwent an extensive gastrointestinal workup and treatment plan without successful control or abatement of symptoms. Upon further questioning, she was found to have been experiencing secondary amenorrhea and body hair changes. Testing revealed panhypopituitarism with severe adrenocorticotropic hormone and cortisol deficiency. She was started on immediate treatment, and her symptoms resolved in less than 24 h. Imaging showed suspected Rathke’s cyst, which has since been removed. Based on similar cases and neuroanatomy, we suspect that her symptoms were due to her severe cortisol deficiency, such that a lack of sympathetic tone leads to increased vagal tone and increased neuronal signals from the brain’s emetic center. This conclusion is further supported by the rapidity of resolution of her nausea and vomiting. This case highlights this rare and severe case of panhypopituitarism and also comments on the importance of a thorough history and physical exam, which ultimately lead to the uncovering of an unexpected diagnosis.