Theodor Morell
In 1938, Hitler demanded control of part of Czechoslovakia.  While Hitler was meeting with the Czechoslovak president, Emil Hacha, Hitler began yelling at Hacha.  Hacha became so scared of Hitler that he fainted.  Morell injected stimulant drugs into Hacha to wake him up.  Morell said these drugs were only vitamins, but they may have included methamphetamine.  Soon after Morell gave him the drugs, Hacha agreed to do what Hitler wanted.