<p>Allergic rhinitis is one of the most common chronic conditions encountered in ENT. Its impact on quality of life is substan-tial.. The concept of the unified airway emphasizes the interconnected nature of respiratory allergic diseases. This study aimed to evaluate the impact of allergic rhinitis on the lower airway by determining the association between allergic rhinitis and bronchial hyper-responsiveness using peak expiratory flow rate. A cross-sectional study was conducted at the allergy clinic, Department of ENT, Bangalore Baptist Hospital, from April to November 2019 among 147 patients aged 18–75 years presenting with symptoms of allergic rhinitis and no prior history of asthma. Patients with nasal polyps or diagnosed bron-chial asthma were excluded. Clinical history, symptom severity, and family history were recorded. PEFR was measured using a standard-range peak flow meter (Breathometer), with the highest of three consecutive readings taken after deep inspiration and compared with age-adjusted expected values. Among allergic rhinitis patients, 43.5% had reduced PEFR (&lt;80% predict-ed). Reduction in PEFR increased with higher TNSS scores, greater disease severity, and family history of bronchial asthma. Moderate-severe persistent allergic rhinitis showed the highest incidence (56.6%), while mild intermittent disease showed the lowest (4.2%). Patients with familial asthma predisposition had a 75% incidence of reduced PEFR. Routine PEFR monitoring is recommended in all allergic rhinitis patients, especially those with moderate-severe disease and positive family history, as a simple, safe, and cost-effective tool for early detection of lower airway involvement.</p>