Introduction: Up to 90% of asthmatic patients have comorbid allergic rhinitis (AR). Although appropriate therapy of AR can improve asthma symptoms and management, AR is often underdiagnosed and under-treated in asthmatics. A non-systematic literature research was conducted on AR as a comorbidity and risk factor of asthma. Latest international publications in medical databases, international guidelines, and the Internet were reviewed. Areas covered: Based on the conducted literature research there is proved evidence of the necessity of diagnosis and treatment of AR in patients with asthma because it affects health care utilization. Therefore, it is recommended in national and global guidelines. Expert opinion: AR increases the risk of asthma development and contributes to the severity of an existing asthma. Early treatment of AR with drugs as intranasal steroids, antihistamines, leukotriene receptor antagonists, and especially allergen-specific immunotherapy can reduce the risk of asthma development and the concomitant medication use in addition to severity of symptoms in AR and asthma.