These studies involved 70 people with Type 1 diabetes and 51 people with Type 2 diabetes. Researchers found blood sugar control was equivalent when inhaled Regular insulin was compared to injected Regular taken before each meal. Although press reports have puffed up this technology, some problems are apparent.
Oral delivery is limited by the acidity of the stomach and digestive enzymes of the intestines.
These problems have stymied researchers for at least 40 years, although a new novel approach discussed below offers some hope. The Real Thing Nasal delivery into the bath towel size area of the upper airways suffers from several problems. Poor transport across the mucous membranes of the nose required either very large doses of insulin or a chemical to enhance insulin transport. When insulin alone was used to deliver 10 units into the blood, about 100 units of insulin would be required, making costs prohibitive. Transport enhancing chemicals create nasal irritation and rhinnorhea.