E. G. Champlin & Co. (E. G. Champlin, George Greenman, & Frank Champlin) was established in 1845 as prescription apothecaries and were also dealing in toilet articles, perfumery, coal oil, lamps, and other such items. They were located at 26 Main Street in Westerly, RI and were still in business in 1875 with Walter Price and Edward H. Burdick listed as druggists and registered pharmacists.

In 1878, Walter Price & Co. (Walter Price, George Greenman, and Charles T. Price) took over E. G. Champlin & Co. and became wholesale and retail druggists and registered pharmacists and remained located at 26 Main Street in Westerly, RI.

By 1890 the company had become Walter Price Patent Medicine Co. and they were putting out patent medicines of all types as well as extracts and their own Compound of Folic Syrup and an Elixir of Life.

In 1898, Greenman left the company and was replaced by Thomas J. Bannon, a former clerk of the company who became a pharmacist in 1894. The listed address was now at 20 Main Street. Besides the medicines, the company also dealt in pharmaceutical items such as trusses, elastic stockings, shoulder braces, and other similar items.

In 1901 Bannon took over the company which by then had expanded to 30 Main Street. Walter Price remained active in the business until his death in 1910.

In 1922, Bannon changed the name of the company to the Bannon Drug Store and relocated to 10 - 12 Canal Street in Westerly.