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Updated: Jan 28, 2026

Symptom Assessment of Patients with Allergic Rhinitis Using an Allergen Exposure Chamber
Published on: March 3, 2023
Add-on probiotics in patients with persistent allergic rhinitis: A randomized crossover clinical trial
Mir Mohammad Jalali1, Robabeh Soleimani2, Ali Alavi Foumani3
1Rhino-sinus, Ear, and Skull base Diseases Research Center, Department of Otolaryngology, Guilan University of Medical Sciences, Rasht, Iran.
Objectives:
Current medications for allergic rhinitis (AR) may have undesirable side effects that could affect quality of life (QoL). Probiotics could be an alternative in these patients. The aim of this study was to assess the impact of add-on probiotics on symptoms and QoL of patients.
Methods:
In this randomized crossover clinical trial, patients with persistent AR were included. Each subject received budesonide with probiotic supplements (BP) or budesonide with placebo for 8 weeks (B), then vice versa for a further 8 weeks. There was an 8-week washout. The primary outcome was the change of the Short Form 36-Item Health Survey (SF-36) score. The secondary outcomes were assessed by the Sinonasal Outcome Test-22 (SNOT-22) and the Control of Allergic Rhinitis and Asthma Test (CARAT) questionnaires.
Results:
A total of 152 subjects (30.1 ± 7.6 years) completed the study. The SF-36 score in both groups showed improvement compared with baseline values. Treatment BP was more effective than that of B. The Cohen's d and the number needed to treat for Physical Component Scales of SF-36 were 0.40 and 10.77, respectively. These values for Mental Component Scales were 0.33 and 12.61, respectively. Also, treatment BP showed more reduction in the score of SNOT-22 and CARAT.
Conclusion:
This study showed that the addition of probiotics to budesonide significantly improved QoL in persistent AR patients. However, the clinical situation of these patients may be not very representative of AR patients in general population. Further studies are recommended.
Level Of Evidence:
1b Laryngoscope, 129:1744-1750, 2019.
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