Phentermine
Phentermine is a sympathomimetic amine anorectic agent and it was introduced in 1959 as part of an anti-obesity combination drug. It is chemically related to amphetamine and it is commonly referred to as an atypical amphetamine. Phentermine has not been reported an addictive potential which allows this agent to be classified under the Schedule IV drugs (low abuse potential).  Phentermine was FDA approved for short-term weight management in 1959 and it became widely used in 1960. This initial product, formed by the combination of phentermine with [fenfluramine] and [dexfenfluramine] was discontinued after finding several reports of abnormal valves in nearly 30% of the consumers. Later on, phentermine was approved alone and in combination with topiramate in 2012 as a new alternative that required lower doses of phentermine to obtain the desired effect.