"Tobacco" does not appear in the US Pharmacopoeia, an official government listing of drugs. "The removal of tobacco from the Pharmacopoeia was the price that had to be paid to get the support of tobacco state legislators for the Food and Drug Act of 1906. The elimination of the word tobacco automatically removed the leaf from FDA supervision."--Smoking and Politics: Policymaking and the Federal Bureaucracy Fritschler, A. Lee. 1969, p. 37
"FDA" in that above quote should actually read the Bureau of Chemistry of the United States Department of Agriculture.