Short answer: Inhaled insulin has a half-life of 120 to 206 minutes (apparent terminal). Levels peak 10 to 20 minutes after a dose. People vary, so treat these as estimates.
Inhaled insulin is human insulin made into a dry powder that is breathed in through the mouth at the start of a meal and absorbed through the lungs. It is sold as Afrezza (MannKind), used with a small Afrezza Inhaler.
Also known as: Afrezza, insulin human inhalation powder.
Afrezza comes in single-use cartridges of 4 units (blue), 8 units (green) and 12 units (yellow). Each cartridge is one inhalation; larger doses use more than one cartridge. An inhaler is used for up to 15 days and then replaced.
The Afrezza label approves it to improve blood sugar control at mealtimes in adults and children 6 and older with diabetes. It is not recommended for diabetic ketoacidosis or in people who smoke or have recently stopped. Label dosing: inhaled at the beginning of each meal. People new to insulin start at 4 units per meal; people switching from injected mealtime insulin use the label's conversion table (for example, up to 3 injected units becomes 4 units of Afrezza). In type 1 diabetes it is always used with a basal insulin. The label has no missed-dose rule.
Afrezza has a boxed warning: sudden airway narrowing (bronchospasm) has been seen in people with asthma and COPD, so it is not used with chronic lung disease, and a medical history, exam and spirometry (FEV1) are done before starting. Lung function is checked again after 6 months and then yearly, because Afrezza causes a small decline in FEV1. The label also warns about lung cancer risk, ketoacidosis and the usual insulin risks, including low blood sugar. Cough was the most common side effect besides low blood sugar: 26% of adults with type 2 diabetes (20% on placebo) and 29% with type 1 (5% on injected insulin). See Afrezza side effects, Afrezza dosing schedule, Afrezza vs Humalog and the glossary entry for inhaled insulin.
The Afrezza label says insulin peaked 10 to 20 minutes after inhaling 4 to 48 units, the apparent terminal half-life ranged from 120 to 206 minutes, and levels were back to baseline after about 60 to 240 minutes. In type 1 diabetes, the effect was first measurable at about 12 minutes, peaked at about 35 to 55 minutes, and returned to baseline after about 90 to 270 minutes, depending on dose.
Numbers shown are taken from the source above. Half-life varies from person to person.
How Dose Track handles peptides · Reconstitution calculator · Half-life calculator