What is an inhaler?

An inhaler is a device used to deliver drugs to the body via the lungs for the treatment or prevention of diseases of the airways such as asthma, chronic obstructive pulmonary disease or cystic fibrosis. However, because the lungs have a good blood supply, inhalers can also be used to get other drugs into the body via the lungs such as treatments for influenza or, more recently, insulin for patients with diabetes. However, most inhalers are used for breathing problems, and as such, the inhaled route is of limited value to patients that have problems swallowing their medicines, as most medicines are not available as inhalers.

Using an inhaler to deliver a drug straight to the lungs where it is needed means it is likely to work more quickly. Smaller doses are also needed rather than using tablets or injections, which reduces the risks of side effects.