Effect of Mouthwash in Reducing the Symptoms Associated With Flu and Cold Viruses

The aim of this study will be to evaluate the efficacy of regular cleaning of the oropharynx (via gargling) on the incidence of symptoms associated with flu and colds. The working hypothesis is that there will be a significant reduction in symptoms associated with flu and colds after using the mouthwash product, compared to the experimental control regime. A total of 150 individuals will be randomized to one of the two experimental regimens and followed for a period of 90 days. The experimental regimen consists of toothbrushing followed by gargling with a cetylpyridinium chloride (CPC) (0.075%) and zinc containing alcohol free rinse and the control regimen consists of toothbrushing alone. Participants will be instructed to brush their teeth twice a day for two minutes. Those allocated to the test regime will gargle with 20 ml of the mouthwash after each brushing. At the initial visit, participants will receive the products and instructions for use, as well as a daily log questionnaire. Participants will be asked to send their daily records once a week, using a messaging application. The proportion of days without any of the evaluated symptoms will be used as the main outcome. In addition, soft and hard tissue exams will be performed at the initial consultation, after 30 and 90 days of follow-up by a blinded researcher. Potential adverse events will be collected throughout the study. The groups will be compared using the chi-square test and one-way analysis of variance (ANOVA) will be used to compare the treatment group symptom rates between groups. The significance level will be set at 95%.