Phendimetrazine (By mouth)


Phendimetrazine (fen-dye-MET-ra-zeen)
Used in combination with a reduced-calorie diet to cause weight loss in people who are obese.

Brand Name(s)

There may be other brand names for this medicine.

Bontril Slow-Release, Bontril PDM, Phendiet, Phendimetrazine Tartrate, Phendiet-105, Bontril

When This Medicine Should Not Be Used

You should not use this medicine if you have had an allergic reaction to phendimetrazine. You should not use this medicine if you have heart disease, high blood pressure, clogged arteries, glaucoma, overactive thyroid, or a history of drug abuse. You should not use this medicine if you have used an MAO inhibitor such as Eldepryl®, Marplan®, Nardil®, or Parnate® within the past 14 days. Do not use this medicine if you are using any other stimulant, appetite suppressant, or diet pill. This medicine is not for use by women who are pregnant, or children who are under 12 years of age.

How to Use This Medicine

Capsule, Tablet, Long Acting Capsule
  • Your doctor will tell you how much of this medicine to use and how often. Do not use more medicine or use it more often than your doctor tells you to.
  • If you are using the extended-release capsule, the usual dose is one capsule each morning. If you are using the immediate-release form of this medicine, the usual dose is one tablet or capsule taken 2 or 3 times per day.
  • Take the medicine 30 to 60 minutes before a meal.
  • Swallow the capsule whole. Do not break, crush, or chew it.
  • This medicine should be used for only a few weeks, or until it no longer suppresses your appetite.
If a dose is missed:
  • If you miss a dose or forget to use your medicine, use it as soon as you can. If it is almost time for your next dose, wait until then to use the medicine and skip the missed dose. Do not use extra medicine to make up for a missed dose.

How to Store and Dispose of This Medicine

  • Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.
  • Ask your pharmacist, doctor, or health caregiver about the best way to dispose of any outdated medicine or medicine no longer needed.
  • Keep all medicine away from children and never share your medicine with anyone.

Drugs and Foods to Avoid

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.
  • Make sure your doctor knows if you are also using guanethidine (Ismelin®), sibutramine (Meridia®), or an MAO inhibitor (Eldepryl®, Marplan®, Nardil®, Parnate®).

Warnings While Using This Medicine

  • Make sure your doctor knows if you are pregnant or breast feeding, or if you have diabetes or high blood pressure.
  • Your doctor will need to check your blood pressure and heart rate at regular visits while you are using this medicine. Be sure to keep all appointments.
  • This medicine may be habit-forming. If you feel that the medicine is not working as well, do not use more than your prescribed dose. Call your doctor for instructions.
  • This medicine may make you dizzy or drowsy. Avoid driving, using machines, or doing anything else that could be dangerous if you are not alert.
  • Do not stop using this medicine unless your doctor tells you to. If you suddenly stop using this medicine, you may feel very tired and depressed.

Possible Side Effects While Using This Medicine

Call your doctor right away if you notice any of these side effects:
  • Change in how much or how often you urinate.
  • Confusion, hallucinations, feelings of panic.
  • Fast, pounding, or uneven heartbeats.
  • Feeling severely restless, jumpy, or irritable.
  • Lightheadedness or fainting.
  • Ongoing trouble sleeping.
  • Skin rash, redness, itching.
  • Tremors or shaking.
  • Unusual thoughts or behavior.
If you notice these less serious side effects, talk with your doctor:
  • Dry mouth, constipation, diarrhea, nausea, stomach pain.
  • Feeling restless, excited, or agitated.
  • Headache, blurred vision.
  • Increased or decreased interest in sex.
  • Mild problems with sleeping.
  • Sweating or flushing.

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088
Review Date: 2011-02-04 Reviewed By: Keywords: ,
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