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By Kristin Hussey on

The Addictive History Of Medicine: The Curious Case Of The 7 Percent Solution

“Which is it to-day,” I asked, “morphine or cocaine?”
He raised his eyes languidly from the old black-letter volume which he had opened.
“It is cocaine,” he said, “a seven-per-cent solution. Would you care to try it?”

The Sign of Four, Sir Arthur Conan Doyle, (1890)

Leatherette case for a cocaine syringe, not unlike the one described by Sir Arthur Conan Doyle (Credit: Science Museum).

Sherlock Holmes is undoubtedly literature’s most famous cocaine user. In Sir Arthur Conan Doyle’s stories, Holmes uses cocaine in order to stimulate his brain when he wasn’t applying it to a case. The detective famously injected a ‘seven percent solution’ which was most often administered by doctors; not surprising considering Conan Doyle was a doctor himself. In the mid-1880s when the author was publishing such stories as A Scandal in Bohemia (1886), cocaine was believed to be a new wonder drug, able to kill pain and improve mental function.

An advertisement expounds the virtues of cocaine for treating teething children. (Credit: University at Buffalo)

In fact, Sherlock Holmes certainly would not have been alone amongst his contemporaries for his use of cocaine. Since 1856 when cocaine had been isolated from the coca plant, the drug was widely used for its pain-killing properties. The drug found its way into such medicines as children’s tooth-ache remedies and was even prescribed to treat morning sickness.

Although his habit was always condemned by Watson, in later stories Holmes himself referred to his hypodermic syringe as an ‘instrument of evil’. Similarly, the recreational use of cocaine fell off sharply at the end of the 19th century as its dangers became apparent. The drug was eventually banned in the UK in 1920.

Bottle of Tabloid brand ‘Voice’ tablets containing cocaine for improving speaking and singing abilities, c. 1890-1910 (Credit: Science Museum).

In the modern BBC adaptation of Sherlock starring Benedict Cumberbatch, there is no mention of the ‘morocco case’ of Conan Doyle’s originals. However, in ‘A Study in Pink’, 221B Baker Street is subjected to a drug raid, and references are later made to Sherlock experiencing withdrawal symptoms. Could this be a nod to the sleuth’s original cocaine habit?



This article was written by Kristin Hussey and Luke Pomeroy, Collections Information Officers