Heinz Edgar Lehmann, OC FRSC (July 17, 1911 – April 7, 1999) was a German born Canadian psychiatrist best known for his use of chlorpromazine for the treatment of schizophrenia in 1950s.
Born in Berlin, Germany, he was educated at the University of Freiburg, the University of Marburg, the University of Vienna, and the University of Berlin. He emigrated to Canada in 1937.
In 1947, he was appointed the Clinical Director of Montreal's Douglas Hospital. From 1971 to 1975, he was the Chair of the McGill University Department of Psychiatry.
From 1969 to 1972 He was one of the five members of the LeDain Commission A royal commission appointed in Canada to study the non medical use of drugs. He was an advocate for decriminalization of marijuana.
He was ahead of his time in that he supported research in the use of the active ingredient psilocybin to alleviate anxiety.
In 1976, he was made an Officer of the Order of Canada. In 1970, he was made a Fellow of the Royal Society of Canada. He was inducted into the Canadian Medical Hall of Fame in 1998.
In 1999, the Canadian College of Neuropsychopharmacology established the Heinz Lehmann Award in his honor, given in recognition of outstanding contributions to research in neuropsychopharmacology in Canada.