• Excess insulin
• Incorrect insulin injection technique
• Increased exercise (relative to usual)
• Gastroparesis and malabsorption
• Excess insulin secretagogues (e.g. sulphonylureas)
• Development of renal failure (with reduced clearance of insulin and sulphonylurea)
• Development of other endocrine disorders (adrenal insufficiency, hypothyroidism, hypopituitarism)
• Early pregnancy and breast-feeding

In patients with or without diabetes mellitus

• Alcohol binge (inhibits hepatic gluconeogenesis)
• Starvation
• Severe liver disease (Chapter 77)
• Sepsis (Chapter 35)
• Salicylate poisoning
• Adrenal insufficiency (Chapter 90)
• Hypopituitarism (Chapter 93)
• Other drugs known to cause hypoglycaemia (e.g. propranolol, salicylates and disopyramide)
• Falciparum malaria (Chapter 33)
• Insulinoma
• Nesidioblastosis (acquired hyperinsulinism due to beta cell hyperplasia)
• Insulin autoimmune hypoglycaemia
• Accidental or non-prescribed use of insulin or insulin secretagogues
• Factitious hypoglycaemia