Twenty adults 18 and up, with allergic asthma will be enrolled. They will have a run-in on 2 weeks of 200 micrograms beclometasone inhaler and then be randomised to add either intranasal fluticasone and azelastine, or placebo nasal spray to their treatment (double blind). Treatment period one will be 3-5 weeks followed by a washout of 2-4 weeks, and crossover to treatment period two for 3-5 weeks. Due to the crossover nature of this study participants will receive both treatments in random order. There will be an Interim analysis after 20 participants complete the study per protocol and the exact required sample size will be recalculated (Pocock/adaptive design).