Inhalation devices, delivery systems, and patient technique.

BACKGROUND: In real-life clinical settings, physicians often consider the properties of various inhaled corticosteroids (ICSs), but typically little consideration is given to the properties of different inhalers and formulations.

OBJECTIVE: To discuss the effects of inhalation devices and user technique on efficacy, safety, and adherence with the aim of improving asthma management.

METHODS: Relevant publications were selected to augment discussion.

RESULTS: There are many types of devices available, each with advantages, disadvantages, ease of use, and rate of misuse. Aerosol particle size influences the deposition pattern of a drug in the lungs, and the optimal particle size range is 1 to 5 μm. Retrospective reviews suggest that smaller particles (1-2 μm) could provide improved asthma control, but randomized, prospective studies are needed. Multiple studies have demonstrated high misuse rates in patients for pressurized metered-dose inhalers and dry powder inhalers. Because of this, repeated education should include physical demonstrations of using the device, checking the patient's technique, correcting the technique, and rechecking the technique. This also means that dedicated, trained staff and placebo devices should be available for instructing patients. Furthermore, the device should be selected to be cost effective and to fit the patient's preference and ability to use it correctly to enhance compliance. Asthma management guidelines and algorithms are available to guide the clinician.

CONCLUSION: The choice of inhaler device should depend on cost effectiveness and the patient's preference and ability to use it correctly. Patient inhaler technique should be checked and, if necessary, corrected and rechecked, with retraining if needed, at every opportunity.