5.1
Overall budget impact is very sensitive to device prescribing patterns, since acquisition costs of inhalers delivering the same class of drug at the same dose vary substantially (as outlined in section 4.11). However, with the exception of spacer devices, it is difficult to predict the impact of the guidance set out in section 1 on local inhaler prescribing patterns and costs. Consequently, an estimate of current inhaler prescribing patterns in primary care is set out below for England and Wales. These prescribing rates and costs can be used together with local information on inhaler use to calculate the likely local cost impact of the guidance. Estimates of the cost impact of the guidance as regards spacer devices are detailed in section 5.5.