Afrezza is the only inhaled insulin available in the United States — a dry-powder rapid-acting insulin inhaled before meals through a small handheld device. It starts working in about 12 minutes, peaks at around 50 minutes, and lasts roughly 3 hours, making it the fastest-onset and shortest-duration rapid insulin on the market. Afrezza requires baseline and periodic lung function testing and is contraindicated in people with chronic lung disease or who smoke. Dose is individualized with a prescriber.
What Afrezza Is
Afrezza is the brand name for human insulin inhalation powder, manufactured by MannKind Corporation. It is FDA-approved as a mealtime (prandial) insulin for adults with type 1 or type 2 diabetes. Originally launched by Sanofi in 2014, Afrezza returned to MannKind in 2016, which has since continued to manufacture and promote it.
Afrezza is unique among insulins because it is inhaled into the lungs rather than injected. The dry powder is delivered through the Dreamboat inhaler — a small whistle-shaped device about the size of a USB drive that holds a single-use cartridge for each dose.
How Afrezza Works
Afrezza uses Technosphere technology — fumaryl diketopiperazine (FDKP) microparticles that adsorb insulin onto their surface in dry powder form. When inhaled into the lungs:
- The Technosphere particles deposit in the deep lung (alveolar region)
- The neutral pH of the lung surface causes the particles to dissolve in seconds
- Released insulin is rapidly absorbed across the thin alveolar membrane into the bloodstream
- The FDKP carrier is eliminated unchanged in the urine
The result is an extremely fast rise in blood insulin levels — faster than any subcutaneous injection — closely mimicking the natural first-phase insulin response to a meal.
Pharmacokinetics: Onset, Peak, Duration
| Parameter | Afrezza (insulin human inhalation powder) |
|---|---|
| Onset of action | About 12 minutes |
| Peak effect | About 50 minutes |
| Duration of action | About 3 hours |
| Recommended timing | At the start of a meal |
| Cartridge doses | 4, 8, and 12 units |
| Bioavailability vs subcutaneous | Different — direct unit conversion not 1:1 |
Who Afrezza Is For
- Adults with type 1 diabetes for prandial coverage, paired with a long-acting basal insulin
- Adults with type 2 diabetes who need mealtime insulin
- People who want to avoid mealtime injections
- People who have post-meal hyperglycemia that does not respond to standard rapid-acting insulin timing
- Adults with normal lung function on baseline spirometry
Who Should Not Use Afrezza
- People with asthma, chronic obstructive pulmonary disease (COPD), or any chronic lung disease — risk of acute bronchospasm
- Current smokers or those who quit smoking within the past 6 months
- People in diabetic ketoacidosis (DKA) — Afrezza is not appropriate; intravenous insulin is required
- Children — Afrezza is not approved for pediatric use
- People with severe baseline reduction in FEV1 (forced expiratory volume in 1 second)
- People with hypersensitivity to insulin or any component of the formulation
Lung Function Monitoring
Because Afrezza is delivered to the lung, lung function testing is part of standard care:
- Baseline spirometry (FEV1) is required before starting Afrezza
- Repeat spirometry at 6 months and then yearly during continued use
- Small FEV1 declines (about 40 mL on average over 2 years in trials) are typical and usually clinically silent
- A drop of 20 percent or more from baseline FEV1 typically prompts discontinuation
How Afrezza Is Used
- Insert a single cartridge (4, 8, or 12 units) into the Dreamboat inhaler
- Inhale once at the start of a meal — about 5 seconds, similar to a brief deep breath
- Remove and dispose of the spent cartridge
- For larger doses, multiple cartridges can be inhaled sequentially (for example, 8 + 4 for 12 total, or 12 + 12 for 24 total)
- Pair with a basal insulin (Lantus, Toujeo, Tresiba, Levemir, or Basaglar) for people with type 1 diabetes
Dose is initiated using the FDA-label conversion table from prior subcutaneous mealtime dose and then refined by the prescriber based on post-meal glucose readings.
Afrezza vs Injected Rapid-Acting Insulins
| Insulin | Route | Onset | Peak | Duration |
|---|---|---|---|---|
| Afrezza (inhaled) | Inhalation | ~12 min | ~50 min | ~3 hr |
| Fiasp (faster aspart) | Subcutaneous | ~2 to 5 min | ~60 min | 3 to 5 hr |
| Lyumjev (faster lispro) | Subcutaneous | ~1 to 3 min | ~60 min | 4 to 5 hr |
| Novolog (aspart) | Subcutaneous | 5 to 15 min | 30 to 90 min | 3 to 5 hr |
| Humalog (lispro) | Subcutaneous | 5 to 15 min | 30 to 90 min | 3 to 5 hr |
| Apidra (glulisine) | Subcutaneous | 10 to 15 min | 60 to 90 min | 3 to 4 hr |
Side Effects
- Cough during or right after inhalation — most common, occurring in about 25 to 30 percent of users; usually mild and improves with continued use
- Throat irritation, dry throat, or hoarseness
- Small declines in FEV1 (lung function) during use
- Hypoglycemia — common, especially within the first 1 to 2 hours after dosing
- Weight gain — modest, similar to other insulins
- Acute bronchospasm — rare but serious, more likely in people with underlying lung disease
- Hypokalemia (low potassium) — possible
- Possible association with lung cancer in trials — small numerical increase observed; FDA notes that no causal relationship has been established
Practical Considerations
- The inhaler is small, portable, and discreet for use in public
- Each inhaler is used for 15 days then replaced
- Cartridges are stored refrigerated and brought to room temperature for use
- Afrezza cannot be used during a respiratory infection until breathing returns to baseline
- Insulin pump users cannot replace pump basal infusion with Afrezza — a long-acting basal injection is still needed
Cost and Access
- Afrezza retail cost is roughly $300 to $500 per month for typical mealtime use
- MannKind offers a copay savings card for eligible commercial-insurance patients
- Patient assistance is available for uninsured or under-insured patients meeting income criteria
- Coverage by commercial insurers, Medicare Part D, and Medicaid varies — prior authorization is common
Storage
- Unopened blister cards: refrigerate at 36 to 46 °F (2 to 8 °C)
- Once a blister card is opened: room temperature up to 77 °F (25 °C) for up to 3 days, then discard remaining cartridges
- Allow refrigerated cartridges to reach room temperature for at least 10 minutes before use
- Inhaler device: use for up to 15 days then replace
- Do not freeze
Related Reading
For broader context, see our treatment overview, the insulin types comparison, and insulin therapy basics.
The Bottom Line
Afrezza is the only inhaled insulin on the US market — a rapid-acting mealtime insulin delivered as a dry powder through a small handheld inhaler. It has the fastest onset (about 12 minutes) and shortest duration (about 3 hours) of any commercial insulin. It is suitable for adults with type 1 or type 2 diabetes who have normal baseline lung function and no chronic lung disease, smoking history, or DKA. Side effects include cough, throat irritation, hypoglycemia, and small FEV1 declines. Baseline and periodic spirometry are required. For the right patient, Afrezza can offer needle-free mealtime coverage and very rapid postprandial glucose control — talk to your prescriber about whether it is appropriate for your situation.
