Methods of treating gastro-esophageal reflux disease in a subject are provided. The methods can include administering an effective amount of a formulation to treat the gastroesophageal reflux disease, the formulation having a water soluble tannin combined with hydrogen peroxide in a pharmaceutically acceptable excipient； wherein, the tannin has a molecular weight ranging from about 170 Daltons to about 4000 Daltons； the tannin:peroxide weight ratio ranges from about 1:1000 to about 10:1； and, the composition at least inhibits a gastrointestinal spasm associated with gastroesophageal reflux disease in the subject when compared to a second subject in a control group in which the composition was not administered.
