Objective: Somatropin is human growth hormone (GH) produced by recombinant DNA technology. Several somatropin products with unique delivery devices are available. When administering the last dose from a device, patients may have an insufficient amount of GH remaining for a full dose. Based on a survey of parents/patients using pen devices conducted at the 2007 MAGIC Foundation Convention, 63% of respondents reported that they were likely to discard this remaining amount left in the cartridge (i.e., waste). easypod, an electronic GH delivery device for somatropin (rDNA origin) for injection (EMD Serono, Inc.), contains a dose spread feature designed to minimize waste. A model was developed to estimate potential GH waste per patient with pen devices and the easypod device and quantify the potential annual economic impact. Methods: Base case model utilizes a daily dose (2mg) reflective of the national mean for all GH pen devices (Wolters Kluwer, 2007). A 10% mechanical loss is applied uniformly across all devices based on the reported mechanical loss in the prescribing information for somatropin (rDNA origin) for injection (EMD Serono, Inc.). Model assumes that the easypod dose spread function (±10%; ±25%; or ±50%) is activated by the clinician (base case utilizes ±25%). This function minimizes waste by automatically adjusting the daily dose (+/-) to optimize the cartridge content; the cumulative average of injected doses is equal to the prescribed daily dose. Annual cost of GH waste per patient for each device is reported (wholesale acquisition cost, Medispan, 2007). Results: Expected annual cost of GH waste per patient was lowest for easypod ($112). Results for pen devices ranged from $794 to $3363 (using largest cartridge size for each product). Results fluctuate depending on daily dose, cartridge size and dose spread assumptions. Conclusion: Cost of GH waste can be an important consideration when evaluating GH devices.