Evaluation of the Efficacy of Oral Calcium Supplementation in Reducing the Severity and Frequency of Symptoms in Patients with Allergic Rhinitis

Abstract

Background: Allergic rhinitis is a common inflammatory disorder characterized by sneezing, rhinorrhoea, nasal itching, and nasal obstruction. The potential role of oral calcium supplementation in reducing allergic rhinitis symptoms requires further clinical evaluation.

Objective: To evaluate the efficacy of oral calcium supplementation in reducing the severity and frequency of allergic rhinitis symptoms compared with placebo.

Materials and Methods: This prospective, randomized, single-blinded, placebo-controlled crossover study was conducted in the Department of ENT, A.J. Institute of Medical Sciences, Mangalore, Karnataka, India, from August 2016 to October 2018. Eighty patients aged 18–60 years with clinically diagnosed allergic rhinitis and an absolute eosinophil count (AEC) greater than 400 cells/µL were included. Participants received oral calcium supplementation (500 mg twice daily) and placebo for separate seven-day periods, with a one-week washout interval. Total symptom scores, individual symptoms, and AEC were assessed before and after each treatment period.

Results: The mean total symptom score decreased from 10.20 to 6.80 following calcium supplementation, representing a reduction of 3.40 points (33.3%). During the placebo period, the score decreased from 10.10 to 9.10, representing a reduction of 1.00 point (9.9%). The descriptive difference in symptom score reductions was 2.40 points in favour of calcium. Sneezing showed the greatest mean reduction (0.80 points), followed by nasal obstruction (0.75 points). The mean AEC decreased from 568 to 510 cells/µL during calcium treatment and from 565 to 552 cells/µL during placebo treatment. Statistical significance could not be established from the available summary data.

Conclusion: Oral calcium supplementation was associated with greater descriptive reductions in allergic rhinitis symptom scores and AEC than placebo. Further controlled studies with appropriate statistical analysis are required to establish its clinical efficacy.