INS and diabetes mellitus: Differential diagnoses for PBH include the use of diabetes drugs such as insulin and sulphonylureas, other drugs such as quinine and hydroxychloroquine, causes of endogenous hyperinsulinaemia such as insulin- or proinsulin-secreting tumours, anti-insulin antibody syndrome and non-hyperinsulinaemic causes of hypoglycaemia such as hypoadrenalism, malnutrition, liver and kidney disease and sepsis.