The metered-dose inhaler Qvar RediHaler helps asthma patients avoid some of typical errors when using dosage aerosols. The active agent is delivered by breath actuation, so that hand-breath coordination, which many patients find difficult, is eliminated. Furthermore, unlike pressurised metered-dose inhalers, the RediHaler requires no priming or shaking but is ready to use upon opening the protective cap. The integrated dose counter displays the number of doses remaining.