To be clear I would make the complaint against anyone who tried to enforce it in Canada, not FIDE. Marijuana would also be a problem because officials, coaches, instructors, arbiters etc. would be required to inform on others if they had knowledge of use.
I had previously read that nicotine was the only substance that was proven to improve chess play.
Does anyone know how many cups of coffee are safe to consume without worries of exceeding the limits according to WADA?