Allergic rhinitis (AR) is a significant health issue that can severely impact quality of life (QoL). The traditional classification of AR into seasonal (SAR) and perennial (PAR) forms is inadequate, as many patients are polysensitized to multiple allergens and experience symptoms beyond seasonal or perennial patterns. The Allergic Rhinitis and its Impact on Asthma (ARIA) classification system, based on symptom duration and severity, better reflects the clinical course of AR. Persistent AR (PER) is defined as symptoms lasting more than 4 days per week for more than 4 consecutive weeks, with mild to moderate-to-severe disease based on QoL and symptom severity. Oral antihistamines are a standard treatment for AR, with second-generation antihistamines offering rapid onset and effectiveness. Levocetirizine, a potent histamine H1-receptor antagonist, has been extensively studied and proven effective in both SAR and PAR. The Xyzal in Persistent Rhinitis Trial (XPERT™) demonstrated that levocetirizine (5 mg/day) significantly improved nasal symptoms, including nasal congestion, within the first week of treatment and maintained these improvements over 6 months. Levocetirizine also improved QoL, was well tolerated, and reduced societal and employer costs. In conclusion, levocetirizine is the best-studied therapeutic option for PER, showing prompt short-term and long-term relief of symptoms, improved QoL, and economic benefits. The ARIA classification system is clinically relevant for managing AR, and long-term studies with levocetirizine in PER show significant benefits in symptom control, QoL, and cost savings.Allergic rhinitis (AR) is a significant health issue that can severely impact quality of life (QoL). The traditional classification of AR into seasonal (SAR) and perennial (PAR) forms is inadequate, as many patients are polysensitized to multiple allergens and experience symptoms beyond seasonal or perennial patterns. The Allergic Rhinitis and its Impact on Asthma (ARIA) classification system, based on symptom duration and severity, better reflects the clinical course of AR. Persistent AR (PER) is defined as symptoms lasting more than 4 days per week for more than 4 consecutive weeks, with mild to moderate-to-severe disease based on QoL and symptom severity. Oral antihistamines are a standard treatment for AR, with second-generation antihistamines offering rapid onset and effectiveness. Levocetirizine, a potent histamine H1-receptor antagonist, has been extensively studied and proven effective in both SAR and PAR. The Xyzal in Persistent Rhinitis Trial (XPERT™) demonstrated that levocetirizine (5 mg/day) significantly improved nasal symptoms, including nasal congestion, within the first week of treatment and maintained these improvements over 6 months. Levocetirizine also improved QoL, was well tolerated, and reduced societal and employer costs. In conclusion, levocetirizine is the best-studied therapeutic option for PER, showing prompt short-term and long-term relief of symptoms, improved QoL, and economic benefits. The ARIA classification system is clinically relevant for managing AR, and long-term studies with levocetirizine in PER show significant benefits in symptom control, QoL, and cost savings.