Efficacy and Safety of Oral Antihistamines for Allergic Rhinitis: Network Meta-Analysis

Area of Science:

• Pharmacology
• Clinical Medicine
• Evidence-Based Medicine

Background:

• Oral H1-antihistamines (OAH) are frequently prescribed for allergic rhinitis (AR).
• Evaluating the comparative efficacy and safety of different OAH is crucial for clinical decision-making.

Purpose of the Study:

• To conduct a systematic review and network meta-analysis.
• To compare the efficacy and safety of individual OAH in patients with AR.

Main Methods:

• Searched multiple databases for randomized controlled trials (RCTs) comparing OAH versus placebo or individual OAH.
• Performed network meta-analysis on symptom scores, quality of life, and adverse events.
• Assessed certainty of evidence using GRADE-NMA for second-generation OAH.

Main Results:

• Included 74 RCTs (21 perennial AR, 53 seasonal AR).
• Cetirizine, ebastine, bilastine, and rupatadine showed high efficacy for nasal symptoms; other outcomes varied.
• Adverse event rates were similar among second-generation OAH; serious events were rare.
• Certainty of evidence was generally low or very low.

Conclusions:

• Some OAH may be more efficacious, but differences between second-generation medications are often trivial.
• No significant differences in safety profiles were found among second-generation OAH.
• Substantial uncertainty exists regarding treatment effects due to low certainty of evidence.