Performance Enhancing Drugs have been involved in sports for over a century, famously being used by eastern Europeans (mostly East Germans & Soviets) during the Olympics in the 1950’s. Recently, Russian athletes have been banned from Olympic participation under the Russian flag due to positive test results as well as complicit/organized planning/use by their federation. Professional baseball has also been recently caught-up in PED use. Other sports such as MMA and boxing have been involved in PED scandals as well.
The reality is that professional sports owners really want players to use steroids since they put on a better show. Players want to use steroids since it approves their performance and shortens recovery from injuries. Fans want athletes to use steroids to see records broken. So why are steroids banned from professional sports in the United States? Quite simply due to safety concerns and because performance-enhancing drugs are banned in the Olympics. Also, “Roid-Rage” has been associated with sudden and unpredictable verbal and physical outbursts.

The best-case scenario has been to let players take performance enhancing drugs under-the-radar but incidents such as the homerun barrage by Mark McGwire, Barry Bonds and Sammy Sosa has made it too obvious. The use of PED’s has been known to insiders since their use in sports began. Currently, the use of PED’s in any sport as well as the Olympics is strictly prohibited and tested for.
Safety has been disputed. Some respected medical professionals have argued that, like many/(all) drugs, PED’s can be safely used. Adding to this theory, many older people have been prescribed human growth hormone as well as testosterone with glowing results. Also, the use of some PED’s for “recovery” is allowed is some sports under specific conditions. Like any drug, misuse can cause many problems up to and including death. Many athletes are using PED’s during the off-season and tapering down just in time for scheduled testing.

Newer PED’s such as Oxygen Carrying Agents (EPO, artificial hemoglobin) have come on the scene and are difficult to test for. One can only imagine what substances are currently used in the shadows.
The legalization of marijuana in some areas has softened the stance on drugs. Also, some states have begun to look-the-other-way for other (non-marijuana) drugs found in small quantities. Even some “harder” drugs like LSD are being “re-tested” for potential benefits.
Is it only a matter of time before PED are allowed? Perhaps. This would end the Cat-and-Mouse testing/finding ways around positive results strategy currently in use.
Please note: most PED’s are legal under medical supervision with a prescription but their use in professional sports is not allowed.