Metformin abuse: A novel and dangerous purging behavior in anorexia nervosa.

Metformin abuse in a patient with an eating disorder as a purging behavior is a rarely reported, albeit very dangerous entity. Clinicians treating eating disorders should increasingly be aware of the potential abuse of prescription medications, unapproved for weight loss but which have weight loss, as a reported side effect. This is particularly important as the ability to obtain prescription medications via the internet, without a prescription, becomes more ubiquitous.