Drugs that work in the brain are considered appetite suppressants. Amphetamines are approved for use in treating other diseases; their use as a weight loss drug is considered "off label" or not approved. Doctors often prescribe drugs for “off-label”…

The use of phentermine and fenfluramine, commonly known as phen-fen, for weight loss increased dramatically in the mid-1990s. Phen-fen usage brought about an impressive increase in the number of medication-dispensing weight loss clinics.

Phentermine is a popular and very effective diet drug, but it can be tricky to spell, particularly if you have only heard of it from your friends and never seen it written in an authoritative place. Unscrupulous Internet retailers take advantage of this…