Dufilho’s most significant contribution to the history and integrity of the field of pharmacy took place in New Orleans in 1816. In 1804, the State of Louisiana, led by Governor Claiborne, passed a law that required a licensing examination for pharmacists wishing to practice their profession.
Prior to this law and before Louisiana became a U.S. State, there were some informal territory licensing measures, but none were enforced. A person could apprentice for six months and then compound and sell his or her own concoctions without any regulations or standards. The public received incorrect doses and erroneous medications. In 1804, Governor Claiborne established a board of reputable pharmacists and physicians to administer a three-hour oral examination given at the Cabildo in Jackson Square.
Louis J. Dufilho, Jr. was the first to pass the licensing examination, therefore making his pharmacy the first United States apothecary shop to be conducted on the basis of proven adequacy.