Dry-powder inhalers (DPIs), as their name implies, dispense medication in a dry-powder formulation. DPIs come in different shapes and sizes and can deliver bronchodilators as well as anti-inflammatory medications.

DPIs are easy to use and very effective, if you operate them properly. The medication particles in the dry powder are so small that they can easily reach the tiniest airways. Keep in mind that, unlike most metered-dose inhalers, with a few types of DPIs, you may not taste or feel the medication when using the device. If you’ve administered the medication properly, however, you will receive its benefit.

Using Your DPI
Although DPIs don’t require using a holding chamber, you’ll need to use your DPI in a specific way. Because every DPI works a little differently, you should make sure you know how to use the one your doctor prescribes. Your physician should instruct you on how to properly use your DPI. The following are general instructions on the proper use of most DPIs:

1. Follow the manufacturer’s instructions to prime your DPI and then load a prescribed dose of the dry-powder medication.
2. Breathe out slowly and completely (usually for three to five seconds).
3. Put your mouth on the mouthpiece and inhale deeply and forcefully.
4. Hold your breath for 10 seconds and then exhale slowly.
5. Repeat the procedure as outlined by your physician until you’ve taken the correct number of doses.

Your DPI is breath activated, meaning you can control the rate at which you inhale the dry-powder medication. However, you do need to inhale with sufficient force in order to assure delivery of the medication to the smallest airways of your lungs. In order to be truly effective, using a DPI requires closing your mouth tightly around the mouthpiece of the inhaler and inhaling steadily, deeply, and forcefully.

Also, make sure the dry powder in your DPI stays dry, to avoid caking or clumping, which can affect the reliability of the dose that is delivered. For DPIs with caps, make sure you always replace the cap after using. Never wash a DPI that still contains medication.

You don’t need to shake your DPI before using it. In fact, shaking some DPIs can result in losing dry powder from those types of devices.

Some of the benefits of using a DPI include:

• Children as young as four can use these devices.
• For many people who have poor metered-dose inhaler technique or who have difficulty coordinating the steps required for properly inhaling medication from a metered-dose inhaler, a DPI is often an excellent alternative (especially for children).
• One inhalation from a DPI often provides the same dosage of a comparable medication as with two puffs from a metered-dose inhaler.
• Because some DPIs have dose counters, it’s easier to tell when your inhaler is almost empty.
• Cold temperatures don’t reduce the effectiveness of DPIs.

Reprinted from Allergies and Asthma for Dummies by William Berger, M.D. Available wherever you buy books.