The goal of this clinical trial is to learn about voice function before and 3 hours after administration of first generation over-the-counter antihistamine in individuals who have been medically diagnosed with allergies and routinely take over-the-counter (OTC) antihistamines for allergy symptoms. The main questions are: 1. Do first generation OTC antihistamines make voice function worse as measured via voice acoustic and aerodynamic measures? It is hypothesized that all objectives measures will reflect a negative change in voice function. 2. Do first generation OTC antihistamines make voice function worse as measured via participant and researcher perceptual measures? It is hypothesized that participants will rate their vocal function as more effortful after taking the antihistamine and researchers will rate voice quality as worse. Participants ages 18-35 who have been diagnosed with allergies, are free of laryngeal pathology, and meet inclusion criteria will be consented. Participation in the study involves a pretrial visit and one day of data collection. The initial visit will obtain informed consent and train the trial measures. The 2nd day involves determination of systemic hydration (\<1.02 g/ml), administration of the OTC antihistamine (Chlor-Trimeton), and measures taken at baseline and 3 hours after antihistamine administration. This antihistamine was selected for its lower sedation and anticholinergic effects than its other first-generation options. Each participant will take one, 12mg tablet. Onset action time for this antihistamine is 3 hours. Participants will be given water to consume during the 3 hour wait for the 2nd data time point to maintain hydration. Measures include routine clinical perceptual, acoustic, aerodynamic, and laryngeal imaging measures.
Age range
18 Years – 35 Years
Sex
ALL
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Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
Urine specific gravity (g/ml)
Timeframe: Start of trial
Fundamental frequency (Hertz)
Timeframe: Change from Baseline Fundamental Frequency at 3 hours
Speaking fundamental frequency (Hertz)
Timeframe: Change from Baseline Fundamental Frequency at 3 hours
Harmonic-to-Noise ratio (decibels, dB)
Timeframe: Change from Baseline Fundamental Frequency at 3 hours
Cepstral peak prominence (decibels, dB)
Timeframe: Change from Baseline Fundamental Frequency at 3 hours
Phonation threshold pressure (cm/H20)
Timeframe: Change from Baseline Fundamental Frequency at 3 hours
Videostroboscopy (video of vocal fold vibration)
Timeframe: Change from Baseline Fundamental Frequency at 3 hours
OMNI-Vocal Effort Scale (scaled score)
Timeframe: Change from Baseline Fundamental Frequency at 3 hours
Rating-of-Fatigue (ROF; scaled score)
Timeframe: Change from Baseline Fundamental Frequency at 3 hours