An insulin injection device, NovoPen, incorporating cartridged U100 Human Actrapid insulin was used in a group of 31 insulin-dependent diabetic patients aged 31.4 +/- 11.2 years (mean +/- S.D.; range 16.5-57.0) to assess its acceptance and suitability in a regimen involving an injection before each of their three main meals plus an evening injection of Human Monotard insulin from a conventional syringe. Twenty-seven patients completed 48 weeks of NovoPen therapy and preferred to continue with the multiple injection regimen in the long term. The device was well accepted and may make multiple injection regimens more feasible.