THE PRACTICE of administering performance enhancing substances to race horses is not new and dates back as far as 3,000 years ago. 
Not until the turn of the 20th century did drugs come under scrutiny as the realization that “doped” horses ostensibly had a competitive advantage. Interestingly the term “doping” and its association with drugs originates from the phrase “getting the inside dope” (i.e. information) and was used to describe handicapping in the 1890’s. 
In the 1800’s, the advent in North America of purified drugs such as cocaine and morphine and their legal and uncontrolled availability established a means of introducing the “medicated” horse to the track for purposes of competitive advantage.
Cocaine a powerfully addictive stimulant, and morphine, a potent opiate analgesic, would be the harbingers of modern drug use in the Thoroughbred. In combination or alone these drugs would serve to increase endurance either by elevating alertness, energy and motor activity or by relieving acute or agonizing pain – a recipe seemingly so effectual that before long the practice of doping made its way to England and other parts of Europe.
"Around the turn-of-the-century (1890-1910), a number of American trainers went to Europe, taking with them these new 'American' medications. As a group, these trainers were so successful that they became known in European racing circles as the 'Yankee Alchemists.' " 
It did not take long for the European and English trainers to protest against the fraudulent American practice of drugging their horses, primarily as a result of their victories over their foreign counterparts.
In England the matter was addressed by the Honorable George Lambton who after repeated attempts to persuade the Jockey Club to contend with the problem took it upon himself to purchase some of the drugs.
With bravado he declared that the English horses would themselves be given medication for the races in which the American horses were participants.  Soon thereafter, in 1903, the Jockey Club of England ruled that running a medicated horse was now an offence against the rules of racing in said country.
Perhaps the greatest significance to the racehorse doping trend in the United States is the story of American trainer Jack Keene, who traveled overseas in quest of reaping the rewards of junked-up racehorses.
"Mr. Keene’s run, however, came to an abrupt halt one day when he was met in the paddock by a Russian racing official, followed by Russian chemist, complete with a basket of frogs. Some saliva was taken from Mr. Keene's horse, and presumably force-fed to the frog, which then reportedly behaved in a most un-frog-like way". 
Unable to race horses in Europe, and now banned from racing horses in Russia, Keene soon returned home to Kentucky and his family farm – Keeneland – where he laid out the track that bears his name, and helped build Lexington into the influential Thoroughbred racehorse breeding and sales center it is today.
North American horse racing is as steeped in tradition as in its drug use.
Continue to Part 3 »
Part 1: Introduction | Part 2: Historical Aspects | Part 3: The Inception of Drug Testing | Part 4: Drugs and Their Actions | Part 5: Policies and Tactics | Part 6: Class 3 Drugs — Performance Enhancing or Not? | Part 7: Class 4 Drugs — Harmless Therapeutics? | Part 8: The Unclassifieds | Part 9: The Call for Reform | Part 10: Who Rules?