1858Poisons Act passed in the UK, governing the supply of poisons to ensure they don't fall into criminal hands
1868Pharmacy Act passed in the US, making it illegal to purchase a number of poisons - among them arsenic, cyanide and opium - without a license
1909Opium smoking is outlawed in the US
1914Harrison Narcotics Act places further stringent controls on opium and cocaine in the US
1920-1933Alcohol is prohibited in the US
1920Dangerous Drugs Act prohibits the importation and exportation of drugs including opium, cocaine and morphine in the UK
1928Drugs Act amended in the UK, adding cannabis (below) to the list of proscribed substances
1961United Nations adopts the Single Convention on Narcotic Drugs, providing a framework for international drug control
1966LSD banned in the US
1971Misuse of Drugs Act passed in the UK, listing proscribed drugs in specific classes and the penalties for their possession
1977Misuse of Drugs Act passed in Ireland, controlling the import, export, production, supply and possession of a range of named narcotic drugs and psychotropic substances