Background In the latter of 20th century, a global growth in allergic diseases has been witnessed, accompanying with spring-out of therapeutic drugs. However, trials did not clarify the comparative effectiveness and pharmaceutical economics of these agents. Severe adverse drug effects have been reported increasingly in the last few years. These made it difficult for clinical practice and selection of national essential drugs. Objective To assess astemizole, loratadine, cetirizine and tefenadine for allergic rhinitis (AR) and urticaria in terms of effectiveness, heart-related drug adverse effects and pharmaceutical economics. Search strategy Cochrane Library, Medline, Embase and Chinese Biomedical Database will be searched. Additional database should be searched for safety and economic studies. Selection Criteria The publication languages are restrained to English and Chinese. 1) Effectiveness: high-quality randomized controlled trials (RCTs) and systematic Reviews (SRs)/ meta-analysis for AR and uritcaria are included, with comparisons restrained to among these four drugs; 2) Safety: a hierarchy of evidences of these four drugs for allergic diseases are included. 3) Economical evaluation: cost-effectiveness and cost-utility assessment of these four drugs for AR and urticaria should be included. Methods of review data extraction sheet and quality appraisal table are separately designed. QUOROM STATEMENT and Jadad Scale are applied, respectively, to SRs and RCTs. Two reviewers independently select the studies, appraise the quality and extract the data. Any disagreement is solved by discussion. Data analysis Fixed effect model is first applied. Sensitivity analysis is employed to study the heterogeneity between trials. Randomized effect model is alternatively used when compromised.