Other breath-activated inhalers are also called dry powder inhalers. These inhalers do derece contain the pressurised inactive gas to propel the medicine. You don't have to push the canister to release a dose. Evidence-based professional reference pages authored by our clinical team for the use of medical professionals. In more http://www.stes.tyc.edu.tw/xoops/modules/profile/userinfo.php?uid=2412854