What are the names of some legal forms of amphetamine and phentermine?

Some examples of legal amphetamines include dextroamphetamine, levoamphetamine, methylphenidate and lisdexamfetamine, according to Amphetamines.com. Phentermine is a legally prescribed stimulant drug that is similar to amphetamines, according to Drugs.com.

Doctors prescribed amphetamines as a treatment for several conditions, including obesity, attention deficit hyperactivity disorder and narcolepsy, explains Amphetamines.com. Amphetamines work by causing the release of adrenalin, epinephrine and norepinphrine in the brain, which reproduces a stimulant reaction. Doctors should consult patients on the habit-forming and addictive nature of amphetamines before prescribing them.

Phentermine is also prescribed as a treatment for obesity, especially those with risk factors such as high blood pressure, diabetes, and high cholesterol, explains Drugs.com. Phenermine is also addictive and should only be used for short amounts of time.