I have been rather unconvinced of the value of inhaled insulin. While it does seem to achieve good control, to date there is no long acting preparation which still has to be injected. Also, as you point out there has been insufficient experience to determine if there might be any long term effect on the lungs. Two final problems are that this insulin should not be used at the time of any respiratory infection and the biological efficiency is only about 20% of injected insulin.so you have to take five times as much insulin for a comparable effect.
A rather better approach is that of insulin conjugated with another molecule which makes it permeable to the mucosa of the mouth (See oralin.). The actual vehicle is much more convenient, but again the biological efficiency is only about 20%.
Neither of these approaches, considering the probable cost, seem to offer any special advance on once a day Lantus (insulin glargine) with mealtime Humalog or Novolog using ultrafine needles.
DOB
