1. Supplementary Figure S1: Comparison of nasal secretion MS cytokine data from the second allergen challenge (of 12 asthmatics with allergic rhinitis) with the ELISA results for the same nasal secretions. Nasal secretion samples were collected before (0 min) and at various times post challenge. Concentrations of IL-5 (a), CXCL8 (b) and CCL11 (c) were measured by both MS and ELISA. Data is presented as median values with interquartile range. Comparisons between MS and ELISA results were by paired T-test for each time point: *p < 0.05; **p<0.01; ***p<0.001.

2. Supplementary Figure S2: Comparison of post nasal allergen challenge cytokine levels in nasal secretions from allergic rhinitis patients with and without asthma. Nasal secretion samples were collected before (0 min) and at various times post challenge. Concentrations of CXCL8 (a), IL-5 (b) and CCL11 (c) were measured by ELISA. Each subject underwent two allergen challenges with results being presented separately. Data is presented as median values with interquartile range. Comparisons between allergic rhinitis only (AR) and allergic rhinitis with asthma (AR+A) patients were by Mann-Whitney test for each time point * p < 0.05.

3. Supplementary Figure S3: Comparison of post nasal allergen challenge cytokine levels in nasal secretions from allergic rhinitis patients with and without asthma. Nasal secretion samples were collected before (0 min) and at various times post challenge. Concentrations of CXCL8 (a), IL-5 (b) and CCL11 (c) were measured by ELISA. Each subject underwent two allergen challenges with results being presented separately. Data is presented as area under the curve (AUC) for each patient with bar showing median levels. Comparisons between allergic rhinitis only (AR) and allergic rhinitis with asthma (AR+A) patients were by Mann-Whitney test: all non significant.

4. Supplementary Figure S4: Comparison of post allergen challenge physiological changes from allergic rhinitis patients with and without asthma. Physiological changes were measured before (0 min) and at various times post challenge. Measurements were taken using nasal secretion weight (a), posterior rhinomanometry (b), acoustic rhinometry (c) and TNSS (d). Each subject underwent two allergen challenges with results being presented separately. Data is presented as median values with interquartile range. Comparisons between allergic rhinitis only (AR) and allergic rhinitis with asthma (AR+A) patients were by Mann-Whitney test for each time point: all non-significant.

5. Supplementary Figure S5: Comparison of post allergen challenge physiological changes from allergic rhinitis patients with and without asthma. Physiological changes were measured before (0 min) and at various times post challenge. Measurements were taken using nasal secretion weight (a), posterior rhinomanometry (b), acoustic rhinometry (c) and TNSS (d). Each subject underwent two allergen challenges with results being presented separately. Data is presented as area under the curve (AUC) for each patient with bar showing median levels. Comparisons between allergic rhinitis only (AR) and allergic rhinitis with asthma (AR+A) patients were by Mann-Whitney test: all non-significant.