The Electronic Sports League (ESL) on Wednesday revealed the full list of drugs it will ban for gaming competitions .

“As the world’s largest and oldest esports organization, ESL has an ongoing commitment to safeguarding both the integrity of our competitions and that of esports as a whole—we wish to ensure we can provide a fair playing field for all participating players,” Ella McConnell, senior editor of ESLGaming, wrote in a statement.

ESL is working with the World Anti-Doping Agency to choose which drugs are prohibited. The current list includes everything from cocaine to steroids to ADHD medication Adderall. Those with legitimate medical reasons for taking Adderall will need proof from a physician.

This follows the ESL’s announcement last month that professional gamers would be tested for performance enhancing drugs, after one player confessed to using the ADHD medication to gain an advantage. As the ESL becomes increasingly popular and prizes get larger, “temptation of rule-breaking [becomes] even greater,” McConnell wrote.

Testing will begin for the first time at the ESL One Cologne this August via skin tests.

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Write to Tanya Basu at tanya.basu@time.com.