Drugs and geniuses

If I lived at the beginning of the 20th century, I would definitely become drug addicted. Drugs were prescribed as medicine and advertisement of the cocaine was put next to the aspirin.

Cocaine was first used by ear, nose and throat doctors and actresses to make their eyes look bigger (it turned out so useful in many ways, huh).
Heroin was first produced in famous "Baier" laboratory and it was advertised as vitamins.
Opium was very popular. It originated in Indonesia (and not in China as many assume). For example, year 1938 man produced 3200 ton opium just in India. It was exported to China, Indonesia and it reached Europa unbelievably soon. First it was used for pain release but than it was found as great creativeness expedient.

Charles J. H. Dickens, William Scott used opium.
Edgar Allan Poe used both opium and alcohol.
Charles P. Baudelaire was one of the first hashish user. He was followed by many others, int. al. J. N. Arthur Rimbaud, Alfred Jarry etc.
Picasso tried everything but his body showed amazing ability to cope with it.

Well-known is event in Sigmund Freud's life when he tried to cure his friend Ernst of a morphine addiction by giving him cocaine as medicine. The result was pretty unpleasant for both Freud's friend and Freud himself - Ernst became addicted to both morphine and cocaine, developed an acute case of "cocaine psychosis" and he died a few years later.

Jean Cocteau was French poet, writer, dramatist, designer and film director. He was original. He was surrealist. And he was totally addicted to drugs. Among his other works he shoot a film "The Blood of a Poet". It was based on dreams, mythology and symbolism. Cocteau used mirror as a way how to get in the other world. He interpreted dreams and visualized how dreams met insanity.
"The Blood of a Poet" was assessed pretty high by the reviewers and now it is known as black-and-white and silent film classic. But in fact it all is based on opium and sometimes psychoanalysis becomes a nightmare. Cocteau was hard drug victim. Is genius stimulated by drugs?

It took a few decades to reveal how harmful is drugs' influence on health.
I will not speak about hippie times and nowadays when all (or almost all) acknowledge the harmful effect of drugs.
It is said that we use about 10% of our brains. I am just wondering, does it really releases some "creative brains" and "wakes up genius in a man"?