3.1
It is important to ensure that an inhaler device delivers the drugs to the airways consistently and in the appropriate quantity. There are a variety of inhaler devices that can be used in the management of asthma: hand-held inhalers that is, pressurised metered dose inhalers (pMDIs; which can be breath activated or manual) and dry-powder inhalation systems (DPIs) and nebulisers. All the metered dose inhaler systems require co-ordination of activation and inhalation and may be difficult to use, particularly for younger children. For this reason, a pMDI should be combined with a spacer device in young children. The purpose of the spacer device is to act as an intermediary chamber into which the pMDI can discharge the drug allowing the child to inhale over several breaths.