Aim of the study: To assess the effect of omalizumab in the management of uncontrolled allergic rhinitis and resistant asthma in patients with concomitant asthma and allergic rhinitis or asthma alone. Methodology: The study was conducted on 100 adult patients with persistent allergic asthma uncontrolled on treatment who were assigned into two groups: group A (50 patients) without clinical evidence of allergic rhinitis and group B (50 patients) with allergic rhinitis uncontrolled on treatment. Patients in both groups were evaluated before the study, after 3, 6 months and one year of starting treatment with omalizumab. Results: In group B patients, statistically significant differences at 6 months compared to baseline were detected in the total nasal symptoms scoring, rescue allergic rhinitis medication use, rhinitis control test, pulmonary function tests, asthma control test, asthma quality of life, rescue asthma medication use and number of asthma exacerbation as p values were significant. Conclusions: Treatment with omalizumab for at least 6 months is needed to achieve improvement of uncontrolled allergic rhinitis and resistant asthma. Omalizumab can be given in allergic rhinitis non asthmatic patients as off-label treatment