Is Phentermine Legal?

By | March 1, 2017

Some people have the misconception that phentermine is an illegal substance, and weight loss pills that contain phentermine are sold illicitly. This is wrong. Phentermine is merely a controlled substance in most countries in the world, including the United States. This means that the manufacture, delivery, dispensation, administration and use of phentermine must be regulated; thus, the need for a prescription prior to purchasing the drug. According to the 1971 Convention on Psychotropic Substances held by the United Nations, phentermine is a Schedule IV substance.

Phentermine belongs to the drug class of amphetamines. Although the chemical structure of phentermine is similar to amphetamine, it is not a kind of amphetamine. However, because of its similarity, phentermine can produce a positive result for drug tests.

Phentermine as a treatment for obesity was initially approved by the Food and Drug Administration (FDA) in the year 1959. At that time, the only available preparation of phentermine was the resin form. Further research and development resulted in the production of phentermine hydrochloride in the 1970s.

Phentermine was formerly manufactured as Fastin by King Pharmaceuticals for the company Smithkline Beecham. However, in December of the year 1998, the drug was taken off the market by SK-Beecham.

Other pharmaceutical companies continue to manufacture weight loss pills containing phentermine. Gate Pharmaceuticals produces Adipex-P, while Medeva Pharmaceuticals sells it as Ionamin. Phentermine is also available as a generic medication.

Aside from these, phentermine is also available in combination with other drugs. Fen-Phen, a cocktail of fenfluramine and phentermine, and Dexfen-Phen, a cocktail of dexfenfluramine and phentermine, were extremely effective as weight loss agents. However, in the year 1997, a report by the Mayo clinic revealed that more than 20 patients taking the cocktails developed valvular heart disease. Further researches revealed that around 30% of patients who were taking dexfenfluramine or fenfluramine alone also developed heart valve disease. The FDA promptly requested the manufacturers of these drugs to withdraw them from the market. Phentermine, on the other hand, remained in the market, as the drug was not noted to cause the aforementioned adverse effect.

A newer cocktail is known as Phen-Pro, a combination of phentermine and Prozac. The mixture results in a longer effect of phentermine. The cocktail has not been shown to cause the same side effects as Fen-Phen. However, at present, the use of the drug has still not been approved by the FDA. The use of Phen-Pro remains “off-label”.

Technically, drugs containing phentermine can only be bought if you have a prescription from a physician. However, it is now possible to buy phentermine weight loss pills even without one. Although it is possible, to do so is illegal. Another act that is illegal is giving or selling one’s phentermine pills to another individual. By doing any of these acts, one can be prosecuted under both the state and the federal laws.

Phentermine is not an illegal drug, but it requires adequate medical supervision. Consult your physician if you plan on using weight loss pills containing phentermine.

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