Suspension Lengths
MLB enforces a three-strike system for PED violations. A first confirmed positive test or violation results in a 50-game suspension without pay. A second violation within a player's career leads to a 100-game suspension. A third violation results in a permanent lifetime ban from professional baseball. These suspensions are enforced immediately and the player cannot play for any MLB team during that period.
Testing Program
MLB conducts random drug tests on players throughout the year, including during the offseason. Players can be tested at any time without advance notice. The league uses both urine and blood tests to detect banned substances. If a test is positive, the player has the right to a second test to confirm the results before any punishment is announced.
Banned Substances
MLB prohibits anabolic steroids, testosterone, human growth hormone, stimulants like amphetamines and cocaine, and other drugs on the World Anti-Doping Agency banned list. The league also bans substances that are not approved by the FDA or that provide unfair athletic advantages. Players are responsible for knowing what substances are prohibited, even if they claim they did not know a product was banned.
The Joint Drug Agreement
The rules for PED suspensions come from the Joint Drug Agreement between MLB and the MLB Players Association, which is the union that represents players. This agreement is renegotiated periodically and outlines how testing is conducted, what substances are banned, what punishments apply, and what rights players have. Both sides must agree to changes in the rules.
Appeals and Grievances
Players who receive a suspension can appeal the decision through a formal grievance process. An independent arbitrator reviews the case, including the test results and any evidence the player provides. The arbitrator can uphold the suspension, reduce it, or overturn it completely. This process can take several months and allows players to challenge false positives or unfair decisions. 
Answer