A multicenter study on the efficacy and safety of So-Cheong-Ryong-Tang for perennial allergic rhinitis.

BACKGROUND

So-Cheong-Ryong-Tang (SCRT), also known as Xiao-Qing-Long-Tang or Sho-seiryo-to, is a mixed herbal formula that is used to treat allergic rhinitis, bronchitis, allergic asthma, and common cold in traditional Korean medicine.

OBJECTIVE

To assess the efficacy and safety of the SCRT for the treatment of allergic rhinitis.

METHODS

We conducted a double-blind, randomized, placebo-controlled, parallel-group, multicenter study of Korean adults with perennial allergic rhinitis. The trial consisted of a 4-week oral administration of SCRT or placebo, with two visits at 2-week intervals, and an 8-week follow-up period, with two visits at 4-week intervals. The primary outcome was a change in the total nasal symptoms score. The secondary outcomes included changes in the Rhinoconjunctivitis Quality of Life Questionnaire score, total serum immunoglobulin E (IgE), cytokines levels, and nasal endoscopy index.

RESULTS

SCRT improved nasal symptoms and quality of life in patients with PAR after 4 weeks medication, and these effects did not last 8 weeks after the end of medication. The level of serum IgE, eosinophil counts, and cytokines did not alter after medication. Nasal endoscopy index did not show significant difference. No serious AEs and safety assessment changes were observed in this trial.

CONCLUSION

SCRT is an effective and safe medication for patients with chronic, perennial, and moderate to severe AR. A clinical study with a >4-week period of medication use, and more participants for immune material test is needed to investigate the long-term efficacy of SCRT in relieving the symptoms of nasal obstruction and identifying the underlying mechanisms of action and indications for traditional Korean medicine.