Definition: Inhaled insulin is mealtime insulin taken as a dry powder breathed in through an inhaler instead of injected. In the US the product is Afrezza. NIDDK lists inhaled rapid-acting insulin as starting in 10 to 15 minutes, peaking at about 30 minutes and lasting about 3 hours.
Afrezza is inhaled at the beginning of each meal, one inhalation per cartridge. Cartridges come in 4 units (blue), 8 units (green) and 12 units (yellow), and larger doses use more than one. An inhaler is used for up to 15 days, then replaced.
| Injected mealtime dose | Starting Afrezza dose |
|---|---|
| Up to 3 units | 4 units |
| 4 to 5 units | 8 units |
| 6 to 7 units | 12 units |
| 8 or more units | 16 units |
Inhaled units are not the same as injected units, which is why the label gives a conversion table. In type 1 diabetes it is always used with a basal insulin.
Afrezza has a boxed warning: sudden narrowing of the airways was seen in people with asthma and COPD, so it is not used with chronic lung disease. Spirometry is done before starting, after 6 months and yearly. Cough affected about 27% of adults on Afrezza against about 5% on comparators, and was the top reason for stopping. The label does not recommend it for people who smoke or recently stopped.
Logging cartridge units rather than injected units, plus the dates of lung tests, keeps the record in the same terms the label uses.
Read more on Dose Track: Who can use inhaled insulin · Afrezza side effects