What Are the Effects?

Only very short studies have evaluated the effectiveness of medications like phendimetrazine. In these studies, people taking these medications lost more weight than those who were not taking them. However, the difference was small (only a fraction of a pound more per week for the people taking the medications). Studies also suggest that the effects of these medications for weight loss decrease after the first few weeks.

When and How to Take Phendimetrazine

General considerations for when and how to take phendimetrazine include the following:
  • The medication comes in the form of a short-acting tablet or a long-acting capsule. The capsules are taken once daily, while the tablets are taken two or three times a day.
  • The long-acting capsules should be taken 30 to 60 minutes before breakfast. The short-acting tablets should be taken one hour before meals.
  • Phendimetrazine should be combined with an appropriate diet. It is not meant to be used without dieting.
  • The short-acting tablets may be split in half, but the long-acting capsules should not be opened, chewed, or crushed.
  • Do not take phendimetrazine more often or in higher doses than prescribed, as this can lead to addiction or dependence.
  • For the medication to work properly, it must be taken as prescribed.

Who Makes It?

Phendimetrazine is currently made by Valeant Pharmaceuticals.

Available Strengths

Phendimetrazine comes in the following strengths and forms:
  • Phendimetrazine 35 mg tablets (short-acting)
  • Phendimetrazine 105 mg capsules (long-acting).
Last reviewed by: Kristi Monson, PharmD
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