Abstract
Background: Type 3c diabetes mellitus (T3cDM) usually occurs because of a variety of exocrine pancreatic diseases with varying mechanisms, which eventually lead to secondary pancreatic endocrine insufficiency i.e. hyperglycemia.
Phenomenology: A man suffering from previously undiagnosed T3cDM presenting with subacute onset hemifacial spasm.
Educational value: This case emphasizes the importance of rapid bedside measurement of capillary blood glucose in patients presenting with acute to subacute onset movements disorders irrespective of their past glycemic status.