Dry powder inhalers are currently available as inhaled bronchodilators (Serevent Diskus® and Spiriva® HandiHaler®) and inhaled corticosteroids (Pulmicort Turbuhaler®, Advair®, Asmanex® and Symbicort®).
The advantage of using a DPI is that it is breath activated, so you do not have to coordinate activating the DPI with inhaling your medication. Instead you simply breathe in quickly to activate the flow of medication. In this way, the breath activated discharge of medication is always properly coordinated with your inhalation. The advantages of DPI use include breath activation, no need to shake the canister and no pollution of the atmosphere with fluorinated hydrocarbons.
It is usually easy to determine the amount of medication remaining in the DPI. Some DPIs work by scraping a precise amount of medication from a drug storage unit contained within the DPI (Pulmicort Turbuhaler®). Others contain each dose of medication in a blister pack or capsule (Advair®, Serevent®, Spiriva® HandiHaler® and Foradil®). They all work well when used properly.
Unlike MDIs, with the optimum inhalation performed slowly, DPIs require that you breathe in quickly to automatically activate the proper flow of medication. You should not breathe out through a DPI because the moisture of your breath can gum up the mechanism. You may also need to more vigorously clean some DPIs than MDIs because powder residue can quickly accumulate.
Since DPIs vary so greatly, you will need to review the specific one prescribed with your physician. However these general rules apply: