Mist misses the mark.

Redesigned asthma inhalers are being introduced as manufacturers begin phasing out the ozone-depleting chlorofluorocarbons that once helped propel asthma drugs into the lungs. Some of the new inhalers use hydrofluoroalkane, an environmentally friendly propellant, while others boast a "breath-activated" design, which requires a sharp, quick inhalation, as opposed to the slow, deep intake of the old inhalers. But some people are finding the latter design hard to use--up to 40% of patients are not using breath-activated inhalers properly, and the full dose of medicine is not reaching the lungs. This may put users at risk for serious asthma attacks, especially those, such as the very young and the very old, who may be less able to coordinate their breathing. Doctors recommend that these patients use inhalers with the alternative propellant.