A 52-year old homeless man presents with intermittent nausea and three episodes of vomiting over the last two days, in a background of epigastric discomfort and heaviness for several weeks. There is no history of fever, urinary symptoms, bowel symptoms, or abdominal trauma.

He had an episode of severe epigastric pain radiating to the back around two months ago, which required emergency admission and hospitalization for a week. No medical records are not available. During admission, he was initially kept nil per oral and given intravenous fluids, and then slowly changed to semi-solids and then solid foods. He is unaware if any medications were administered.

His medical and surgical histories are otherwise unremarkable. He does not smoke, but has been a heavy drinker for over a decade, spending whatever money which comes into his hands on alcohol.

A complete blood count and c-reactive protein levels are both within normal parameters.