Inhalable insulin was available from September 2006 to October 2007 in the United States as a new method of delivering insulin, a drug used in the treatment of diabetes, to the body. After the withdrawal of the only inhalable formulation, all currently available insulin formulations are administered by subcutaneous or intravenous injection.

The first such product to be marketed was Exubera, a powdered form of recombinant human insulin, delivered through an inhaler into the lungs where it is absorbed. Once it has been absorbed, it begins working within the body over the next few hours. Diabetics still need to take a longer acting basal insulin by injection. - cost of £1,100 per person per year.

A systematic review concluded that inhaled insulin "appears to be as effective, but no better than injected short-acting insulin. The additional cost is so much more that it is unlikely to be cost-effective." In October 2007, Pfizer announced that it would be discontinuing the production and sale of Exubera due to poor sales. Several other companies are developing inhaled forms of the drug to reduce the need for daily injections among diabetics.