Pen injector for insulin-requiring diabetic patients.

To compare the metabolic control and acceptability of a pen injector to the traditional syringe used in diabetes, 12 non-insulin-dependent diabetes mellitus (NIDDM) patients and six insulin-dependent diabetes mellitus (IDDM) patients were followed-up at the outpatient clinic of the Taipei Municipal Yang-Ming Hospital. All patients participated in a four-week run-in period and 24-week randomized cross-over design study. Human NPH insulin (Protaphane HM) in vials and in penfills were used in each 12-week experimental period, respectively. Metabolic control was assessed by a biochemical examination (before and after seven months of treatment) and HbA1c levels (at Weeks 1, 4, 16 and 28) and was found to be unchanged. The overall mean blood glucose declined slightly in both treatment modalities but not to a significant level (mean +/- SE; run-in: 175 mg/dL +/- 10 mg/dL; pen: 159 mg/dL +/- 8 mg/dL; syringe: 156 mg/dL +/- 7 mg/dL). The number of hypoglycemic episodes and self-adjustments of insulin dosage did not differ significantly between pen and syringe treatments. At the end of the study, a questionnaire revealed that eight patients would choose pen injectors, nine patients syringes and one was unsure of what to use as a future preference. The limitation of 36 units per injection of insulin is a drawback for those NIDDM patients with insulin resistance. An insulin delivery device that would allow an injection of a larger quantity of insulin is desirable for some patients.