Abuse of central nervous system (CNS) stimulants is common. Addiction to some CNS stimulants can quickly lead to medical, psychiatric, and psychosocial deterioration. Drug tolerance, dependence, and sensitization as well as a withdrawal syndrome can occur.
The judicial branch decides what amendments are unconstitutional as well as acts of the president. However, if the judicial branch were to declare an act of the president unconstitutional, it would mean that Congress agreed to this act.
But these appointments must be approved by the Senate. The Congress can pass a law, but the President can veto it. The Supreme Court can rule a law to be unconstitutional, but the Congress, with the States, can amend the Constitution. All of these checks and balances, however, are inefficient. But that's by design rather than by accident.