Amphetamines

The amphetamines dextroamphetamine (Dexedrine), methamphetamine (Desoxyn), and phenmetrazine (Pleudin) were used most often in the past but are no longer prescribed for weight loss. These drugs elevate mood and produce some modest weight loss over the short term, but present serious risks of addiction, agitation, and insomnia.

Sympathomimetics

Sympathomimetics are agents that act like the neurotransmitter norepinephrine (a stress hormone). Less addictive and possibly safer than amphetamines, these drugs still raise blood pressure. They are approved for short-term use and include phentermine (Ionamin, Adipex, Fastin), diethylpropion, mazindol (Mazanor, Sanorex), benzphetamine (Didrex), and phendimetrazine (Adipost, Botril, Melfiat, Plegine, Prelu-2, Statobex). Phentermine has been withdrawn from the UK market but not the US.