An Update on Insulin Injection Devices

Background: Over the past 15 years, it has become clear that better glycemic control can lead to a substantial reduction in diabetic complications and that such control often requires the use of insulin therapy. However, a number of barriers exist to starting such therapy in patients with diabetes mellitus (DM). Many of these barriers to treatment are related to the use of a syringe to inject the medication. In the past ~20 years, various "pen" devices have become available that help to reduce the stigma associated with insulin injection, allowing more patients to achieve the glycemic control that they require.Objectives: This article provides an overview of the various pen devices available in the United States for subcutaneous insulin delivery and discusses the benefits these devices can provide to patients; their disadvantages are also discussed. Third-party reimbursement for these devices is highlighted.Methods: A MEDLINE search was performed (1980-2007) to identify relevant articles (English-language only) using appropriate key terms, including insulin pen and insulin delivery device. Technical specifications and availability information for the various pen devices were obtained directly from their manufacturers. Insurance coverage data were provided by major national insurance carriers.Results: There are a number of excellent pen devices available for administering each of the currently offered basal and bolus insulin analogues as well as neutral protamine Hagedorn and regular insulins. These devices range from disposable pens—which are supplied to the patient prefilled from the pharmacy, used until empty, and then discarded—to refillable digital pens, some of which have the ability to “remember” prior insulin doses. Data from various studies indicate that both patients and their physicians generally prefer insulin pens over the traditional vial and syringe delivery method. These devices are simple to use, allow patients to be more discreet in social situations, can easily be carried in a shirt pocket or purse, do not need to be refrigerated while in use, are associated with a lesser degree of injection anxiety, and may even be more accurate at lower doses. They may also be the preferred delivery system for the visually impaired, given their larger displays and the audible/tactile “click” produced each time the dose is increased by 1 U. Insulin pens lead to increased patient confidence and satisfaction and improved attitude toward insulin therapy. Most major insurance plans provide some coverage for the disposable pens as well as the cartridges for refillable pens, but this is often under tier 2 and some insurers may require prior authorization.Conclusions: Insulin pens provide DM patients with a number of advantages over a vial and syringe and can often help them overcome major barriers to the initiation of insulin therapy. The use of insulin pens leads to increased patient compliance and potential improvements in glycosylated hemoglobin, but data on glycemic control are not available. The pens should be offered to virtually all patients who require insulin therapy, except in instances in which these pens are financially prohibited.