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Prescription Medication


Learn All About the Study Drug

Phentermine is one of the most commonly prescribed drugs for the treatment of obesity. It was approved by the FDA in 1959, making it the oldest option for treatment. Since its approval in 1959, Phentermine has only been approved for the short-term use of no more than 12 weeks at a time. Taking the medicine this way doesn’t match up with modern recommendations for treatment of obesity. Current recommendations say that medicines for obesity should be used longer, just like we would do for other diseases like high blood pressure or diabetes. LEAP will test whether phentermine can be taken for longer periods of time.

Phentermine Quick Facts

  • It is the Most Commonly-Prescribed Anti-obesity Medication (AOM) in the U.S.

  • In the 1990’s, doctors started prescribing phentermine in combination with fenfluramine to create what was known as Phen-Fen.

  • Phentermine is a stimulant and it’s chemically similar to the stimulant amphetamine

  • Phentermine belongs to a class of drugs called anorectics, also known as appetite suppressants.

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