The effect of Chinese herbal medicine for treatment of allergic rhinitis : a randomized controlled trial

Abstract

Background: Allergic rhinitis (AR) affects 10 to 40% of the general population of all ages and gender. Its symptoms, including running nose, nasal blockage, and sneezing, impose physical, psychological, and social impacts. Western medications, whilst alleviating symptoms, may induce mild to moderate complications. Therefore, herbal medicines have recently been investigated as an alternative treatment of AR. However, limited clinical trials of herbal medicine did not take personal syndromes and body constitution (BC) into account upon prescription. These are important in achieving long-term sustainable therapeutic effect, necessitating an herbal formula based on personal syndromes and BC under the principles of theories, therapies, formulae, and drugs in Chinese medicine. Aim: This clinical trial was to evaluate and compare the effectiveness of Cure-Allergic Rhinitis Syrup (CS) (治敏膏) and Modified Yuping-fen San (MYS) (玉屏風散) on allergic rhinitis, with a Placebo. Nursing students were included and outcome measured, immediately, 1-month and 3-month, after the intervention. Design: A double-blinded Randomized Controlled Trial with repeated-measures, three-arm (i.e., CS, MYS and Placebo) design was conducted. The participants with 'Qi-deficiency' and/or 'Yang-deficiency' types of the syndrome and BC were invited to undertake a 4-week treatment, with one dose per day, of either CS (12 herbs), MYS (6 herbs) or Placebo. Outcomes were measured on four occasions over the period. The primary outcome (symptom severity) was assessed by the Rhinoconjunctivitis Quality of Life Questionnaire Standard (RQLQ-S) using visual analogue scales. Four secondary outcomes including the types of syndrome, BC, perceived quality of life and use of Western medicine were measured. These were evaluated by a Chinese medicine practitioner, a Constitution in Chinese Medicine Questionnaire, the RQLQ-S rated on 7-point Likert scales, and self-reporting, respectively. Results: Of the 249 participants, 240 have completed the trial with nine (3.6%) drop-outs. The Generalized Estimating Equation test and pairwise contrasts tests, indicated that the CS group had a significantly greater reduction of symptoms (mean difference of CS vs. Placebo= 26.13 - 34.54, p<0.0005), and improvements in QoL (mean differences of CS vs. Placebo= 12.81 15.86, p<0.003) and Qi-deficiency, Yang-deficiency and Inherited Special BC (mean differences of CS vs. Placebo= 7.87 5.70, 8.53 6.90 and 5.22 7.14, p= 0.03 0.002, 0.02 0.006 and 0.03 - 0.003, respectively) in the three post-tests. The MYS group also showed significantly greater improvement in some subscales of symptom severity and QoL over the 12-week follow-up. However, the therapeutic effect of MYS was less sustainable (i.e., smaller effect sizes of <0.20) regardless of the variety of syndromes and BCs.Conclusion:Cure-Allergy Rhinitis Syrup can effectively alleviate symptoms and enhance QoL amongst nursing students suffering from AR manifested as Qi-deficiency and/or Yang-deficiency. CS appears to be better than the commonly used MYS in balancing BCs of Qi-deficiency, Yang-deficiency and Inherited Special. This suggests an earlier and more sustainable effect on AR amongst young adults. Further controlled trials on Chinese and/or Asian populations with AR necessitate coverage of a wider range of socio-demographic status, ethnicity, illness characteristics and a longer period of follow-up.