Guerin’s Pharmacy, located in downtown Summerville, is the oldest pharmacy in South Carolina, having operated as an independent pharmacy since 1871. A pharmacist from Charleston, Dr. Schwettman, moved his business to Summerville during the civil war. Upon returning to Summerville after completing his service to his country, Dr. Henry C. Guerin purchased the Summerville side of the business and Dr. Schwettman returned to Charleston. Dr. Joseph A. Guerin, son of Dr. Henry C. Guerin, took over ownership upon the death of his father. Dr. Herbert F. Dunning worked with Dr. Joseph A. Guerin from whom he purchased the business. Charles H. Dunning, Jr. began working for his uncle and Dr. Joseph A. Guerin at the age of 12. He purchased the business from his uncle’s estate in 1975.

After his death in 2014, his daughter, Barbara A. Dunning, is the owner and pharmacist in charge. Working alongside her is Joshua Kister, Pharm D, who has been with Guerin’s since 2009. In September 2017, Guerin’s was bestowed a historical South Carolina marker by the Summerville Preservation Society. It is located outside of the pharmacy on the Richardson side of the building.