Substituted amphetamines are a class of compounds based upon the amphetamine structure; it includes all derivative compounds which are formed by replacing, or substituting, one or more hydrogen atoms in the amphetamine core structure with substituents. The compounds in this class span a variety of pharmacological subclasses, including stimulants, entactogens, hallucinogens, among others. Examples of substituted amphetamines are amphetamine (itself), methamphetamine, ephedrine, cathinone, MDMA (ecstasy), and DOM (STP).