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Phendimetrazine: Phendimetrazine is another sympathomimetic amine approved for short-term use as an appetite suppressant. It works similarly to phentermine and was approved by the FDA in 1961. Side effects include dizziness, dry mouth, and increased heart rate.

Phendimetrazine is a commonly prescribed alternative to phentermine.
Era of Discovery


Mechanism of Action

Sympathomimetic amine that suppresses appetite

History of Use in the United States

Approved by FDA in 1961 and still in use

Benefit of Weight Loss Agent or Medication

Weight loss due to appetite suppression

Possible Side Effects

Dizziness, dry mouth, increased heart rate

Current Regulatory Status in US

Available by prescription

Phendimetrazine: A Comprehensive Overview

Phendimetrazine is another widely used weight loss medication, but unlike phentermine, it has not enjoyed the same level of popularity. Despite this, its rich history and its critical role in obesity management merit exploration.

The drug's development came after the widespread use of amphetamines post World War II, as the scientific community sought safer alternatives with fewer side effects and a lower potential for misuse. The U.S. Food and Drug Administration (FDA) first approved phendimetrazine in 1961. Like phentermine, it was designed to be used as a short-term adjunct to a comprehensive weight loss strategy consisting of dietary modifications and increased physical activity.

The primary function of phendimetrazine is appetite suppression, achieved by stimulating the release of brain chemicals that reduce hunger signals. It belongs to the class of drugs known as sympathomimetic amines, similar to amphetamines. However, phendimetrazine is considered a prodrug - it isn't active in its ingested form and is metabolized in the body into phenmetrazine, which exerts the therapeutic effects.

In the 1950s and 1960s, phendimetrazine was widely marketed under various brand names, such as Bontril and Plegine. However, phendimetrazine soon garnered attention for its potential for misuse. Recognizing this, the Drug Enforcement Administration (DEA) classified it as a Schedule III controlled substance, a category for drugs with a moderate to low potential for physical and psychological dependence. This decision reflected the balance between acknowledging its effectiveness for weight loss and the need to manage its potential for misuse.

Phendimetrazine hasn't received as much attention or scrutiny as other weight loss medications, partly because it hasn't been involved in any major drug controversies like the 'fen-phen' debacle in the 1990s. Its lower profile has allowed it to remain a reliable option for weight loss, and it is still prescribed today, often for patients who do not respond adequately to phentermine.

Today, phendimetrazine is available in two forms: as a 35mg immediate-release tablet to be taken two to three times daily, and as a 105mg extended-release capsule for once-a-day use. Although it is not as commonly prescribed as phentermine, it serves as a valuable alternative for patients seeking medical weight loss solutions.

In conclusion, while phendimetrazine may not be as well-known as other weight loss drugs, its efficacy and utility in managing obesity are undeniable. Its unique characteristics and potential benefits may make it the right choice for certain individuals. As always, the decision to use any medication should be based on a thorough understanding of its benefits, risks, and appropriateness for each patient's unique circumstances.

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