 It is estimated that sale of patent medicines containing opiates decreased by 33% after labeling was mandated.In 1906 in Britain and in 1908 in Canada "laws requiring disclosure of ingredients and limitation of narcotic content were instituted".The Harrison Narcotics Act of 1914 restricted the manufacture and distribution of opiates, including laudanum, and coca derivatives in the United States; this was followed by France's "Loi des stupefiants" in 1916, and Britain's Dangerous Drugs Act in 1920.