Objective: The potential benefit of alkaline water as an adjunctive means of management for symptoms of laryngopharyngeal reflux (LPR) has been of interest for several years. Research suggests that waters with a pH of 8.8 or higher may deactivate pepsin which is thought to be an element of laryngeal irritation resulting in throat discomfort, globus, and chronic throat clearing and cough. Alkaline water may be a useful treatment option for patients with symptoms of LPR, however the pH reliability and stability of commercially available alkaline waters is not well described. This study aimed to measure the pH of several commercially available alkaline waters and track the stability of pH over a two-week period. If these waters are to be of benefit, it is critical to determine if the pH level is as advertised, as well as how long the pH will remain at the threshold 8.8 level after container unsealing.
Methods/Design: 8 of commonly available alkaline waters were tested immediately after bottle opening, and at 24 time points over a two-week period. Tap water, spring water, and distilled water samples were also tested. The pH of each water type was measured in 24-hour periods under the following conditions: 1. no influence sample, 2. contaminated sample (drinking directly from bottle), 3. cold temperature influenced sample (refrigerated), and 4. open air exposed sample (stored without capping). pH testing was completed using an Ohaus ST300 pH Meter (Item #83033961) with a measurement range of 0.00 – 14.00 pH, accuracy (±) of 0.01 pH, and built-in temperature compensation. Prior to each testing point, the probe was calibrated using a 3-point calibration protocol. Statistical significance for time of testing will be calculated. Interactions of testing conditions and time will also be tested. Data collection will be completed by December 2024.
Results: It is hypothesized that time will be a significant factor resulting in lowered pH of all waters.
Conclusion: Alkaline waters may be beneficial in mitigating symptoms of LPR. This study will add data to help determine what waters may provide patient benefit by determining which waters have a pH of 8.8 or higher and if pH drops after bottle opening. Recommendations may be determined for a best “window of use” for alkaline waters.