First-Generation OTC Antihistamine Use and Voice Function: A preliminary study

Abstract

Objectives/Hypothesis: The primary goal of this investigation was to characterize the effect of the first-generation, over-the-counter antihistamine, Chlor-Trimeton on laryngeal structure and function. Study Design: Prospective within-participant multimodality repeated measures design. Methods: Eight consented participants (seven females, one male) completed the study. Volunteers completed the following measures before and 2 hours after antihistamine: perceptual vocal function measures, phonation threshold pressure, acoustic measures, and laryngeal imaging. Paired t-tests were used to determine statistical significance of change pre- and post-administration of the antihistamine. Laryngeal imaging data were descriptively analyzed. Results: A positive correlation between the OMNI-Vocal Effort Scale and the Rate of Fatigue index was identified. No other significant differences were identified for any measures taken. Descriptively, all participants had evidence of mucosal changes in the form of one or more of the following: increased vascularity, mucus in the anterior commissure, and vocal fold color changes (i.e., white to red), all of which are consistent with prior descriptions of allergy larynx. Conclusions: Empirical study of laryngeal appearance and function changes post administration of a commonly used OTC antihistamine affirmed clinical observations of laryngeal tissue changes that have been considered typical for individuals with upper airway allergies. Further study of this population with and without diagnosis of voice impairment is warranted.