The similarities between the two are: Both are used to improve performance and appearance, most are ineffective and expensive, and many are dangerous. The differences between them are: Drugs undergo stringent government testing and are approved by the FDA. Supplements are marketed without any testing for safety or effectiveness and the FDA can take action against unsafe supplements after they are on the market.
Drugs and supplements are similar in that both have an effect on the nervous system and that both are psychoactive substances. They are different in that drugs are often necessary to help someone overcome an illness, while supplements are optional and not necessary.
