Skip to Content

Bontril Slow Release

Generic Name: phendimetrazine (fen di MEH tra zeen)
Brand Name: Adipost, Bontril PDM, Bontril Slow Release, Melfiat

What is Bontril Slow Release?

Bontril Slow Release is similar to an amphetamine. This medicine stimulates the central nervous system (nerves and brain), which increases your heart rate and blood pressure and decreases your appetite.

Bontril Slow Release is used as a short-term supplement to diet and exercise in the treatment of obesity.

Bontril Slow Release may also be used for purposes not listed in this medication guide.

Important Information

Weight loss during pregnancy can harm an unborn baby, even if you are overweight. Do not use Bontril Slow Release if you are pregnant.

Bontril Slow Release may cause blurred vision or impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert and able to see clearly.

Bontril Slow Release may be habit-forming and should be used only by the person for whom it was prescribed. Keep the medication in a secure place where others cannot get to it.

Do not stop using Bontril Slow Release suddenly after long-term use, or you could have unpleasant withdrawal symptoms. Ask your doctor how to avoid withdrawal symptoms when you stop using this medicine.

Do not crush, chew, break, or open the extended-release capsule. Swallow it whole. Breaking or opening the pill may cause too much of the drug to be released at one time.

Before taking this medicine

Do not use Bontril Slow Release if you have used an MAO inhibitor such as furazolidone (Furoxone), isocarboxazid (Marplan), phenelzine (Nardil), rasagiline (Azilect), selegiline (Eldepryl, Emsam, Zelapar), or tranylcypromine (Parnate) in the last 14 days. A dangerous drug interaction could occur, leading to serious side effects.

You should not use this medication if you are allergic to Bontril Slow Release, or if you have:

To make sure you can safely take Bontril Slow Release, tell your doctor if you have any of these other conditions:

Bontril Slow Release may be habit forming and should be used only by the person for whom it was prescribed. Never share this medicine with another person, especially someone with a history of drug abuse or addiction. Keep the medication in a place where others cannot get to it.

FDA pregnancy category X. Weight loss during pregnancy can harm an unborn baby, even if you are overweight. Do not use Bontril Slow Release if you are pregnant. Tell your doctor right away if you become pregnant during treatment.

It is not known whether Bontril Slow Release passes into breast milk or if it could harm a nursing baby. You should not breast-feed while you are using this medicine.

Bontril Slow Release should not be given to a child younger than 17 years old.

How should I take Bontril Slow Release?

Take exactly as prescribed by your doctor. Do not take in larger or smaller amounts or for longer than recommended. Follow the directions on your prescription label. Bontril Slow Release should be taken only for a short time, such as a few weeks.

Bontril Slow Release is usually taken once daily. Follow your doctor's instructions.

Take Bontril Slow Release on an empty stomach, 30 to 60 minutes before your morning meal.

Do not crush, chew, break, or open the extended-release capsule. Swallow it whole. Breaking or opening the pill may cause too much of the drug to be released at one time.

You should lose at least 4 pounds during the first 4 weeks of taking Bontril Slow Release and eating a low calorie diet. Tell your doctor if you do not lose at least 4 pounds after taking the medication for 4 weeks.

Do not stop using Bontril Slow Release suddenly after long-term use, or you could have unpleasant withdrawal symptoms. Ask your doctor how to avoid withdrawal symptoms when you stop using this medicine.

Never take more of this medication than is prescribed for you. Too much Bontril Slow Release could be very dangerous to your health. Talk with your doctor if you have increased hunger or if you otherwise think the medication is not working properly. Taking more of this medication will not make it more effective and can cause serious, life-threatening side effects.

Store at room temperature away from moisture and heat. Keep the bottle tightly closed when not in use.

What happens if I miss a dose?

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

A dose taken too late in the day will cause insomnia.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222. An overdose of Bontril Slow Release can be fatal.

Overdose symptoms of a Bontril Slow Release overdose include nausea, vomiting, diarrhea, stomach cramps, confusion, panic, hallucinations, extreme restlessness, feeling tired or depressed, ringing in your ears, chest pain, slow heart rate, weak pulse, fainting, seizure, or slow breathing (breathing may stop).

What should I avoid while taking Bontril Slow Release?

Bontril Slow Release may cause blurred vision or impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert and able to see clearly.

Drinking alcohol can increase certain side effects of Bontril Slow Release.

Bontril Slow Release side effects

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Stop using Bontril Slow Release and call your doctor at once if you have a serious side effect such as:

  • feeling short of breath, even with mild exertion;

  • chest pain, feeling like you might pass out;

  • swelling in your ankles or feet;

  • pounding heartbeats or fluttering in your chest;

  • confusion or irritability, unusual thoughts or behavior;

  • feelings of extreme happiness or sadness; or

  • dangerously high blood pressure (severe headache, blurred vision, buzzing in your ears, anxiety, confusion, chest pain, shortness of breath, uneven heartbeats, seizure).

Less serious side effects may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

See also: Side effects (in more detail)

What other drugs will affect Bontril Slow Release?

Tell your doctor about all other medicines you use, especially:

This list is not complete and other drugs may interact with Bontril Slow Release. Tell your doctor about all medications you use. This includes prescription, over-the-counter, vitamin, and herbal products. Do not start a new medication without telling your doctor.

Where can I get more information?

  • Your pharmacist can provide more information about Bontril Slow Release.
  • Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.
  • Disclaimer: Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Copyright 1996-2012 Cerner Multum, Inc. Version: 8.02.

Date modified: January 03, 2018
Last reviewed: April 25, 2012

Hide