Effects of intrapulmonary insulin in patients with non-insulin-dependent diabetes

The effects of intrapulmonary insulin administration in non-insulin-dependent diabetes mellitus (NIDDM) were studied in 12 patients in a double-blind randomized placebo-controlled intervention study. Regular human insulin, 100 U ml(-1), was given as an aerosol by oral inhalation after a 12-h fasting. A significant decrease in blood glucose concentration,from 10.2+/-0.5 to 6.1+/-0.5 mmol l(-1) (p<0.0001) and a significant rise in serum insulin concentration, from 11.2+/-1.8 to 28.0+/-2.6 mU ml(-1) (p<0.0001), was seen. Serum C-peptide levels decreased from 1.6+/-0.2 to 1.0+/-0.1 nmol l(-1) (p<0.0001). No side-effects were reported following aerosol inhalation. If similar results can be obtained when using this route for insulin administration to insulin-dependent diabetes mellitus patients, this may be a useful complement to traditional subcutaneous insulin injections in these patients.