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Drug Class: Commonly Known As: Category:
Antiobesity Agent Adult

Phentermine - What is it for

Phentermine is an anorectic agent (an agent that suppresses appetite). It is used in the management of obesity as a short-term adjunct in a comprehensive regimen of weight reduction, which includes diet and exercise.

Phentermine - Side Effects, Precautions, and Contraindications

What side effects can Phentermine cause?

Common side effects include:

  • Abdominal pain, nausea, vomiting, diarrhoea or constipation
  • Dry mouth and unpleasant taste
  • Palpitations and increased blood pressure
  • Headache, restlessness or tremor

Inform your doctor if the side effects above become severe and bothersome.

Stop the medication and inform your doctor immediately if you experience any allergic reactions (e.g. rash, swelling of the eyes or lips, difficulty breathing).

Before taking Phentermine , what precautions must I follow?

​Inform your doctor if you are taking any other medications, such as medications affecting the heart, high blood pressure medications or antidiabetic medications.

What food or medicine must I avoid when I take Phentermine ?

Phentermine - Dosage and How to Use

How should Phentermine be used?

Phentermine comes in capsule form, to be taken by mouth.

It should be taken in the morning, before breakfast or 1 to 2 hours after breakfast. Avoid taking late in the evening as it may cause insomnia (difficulty sleeping at night).

Take this medication as instructed by your doctor. Do not exceed the recommended dose to increase the effect as it may cause other side effects.

What should I do if I miss a dose?

Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and take only your regularly scheduled dose. Do not take a double dose to make up for the missed one.

What should I do if I overdose?

Phentermine - Handling

How should I handle Phentermine safely?

Phentermine - Storage

How should I store Phentermine ?

;#Keep away from children;#Keep in a cool, dry place, away from direct sunlight;#Store at room temperature;#

How should I dispose of Phentermine safely?

Phentermine - Additional Information

Phentermine should be used with caution in those with mild to moderate hypertension (high blood pressure). In the first days of treatment, ensure that there is no loss of control or fluctuations in blood pressure.

Phentermine should not be used if you are intending to become pregnant, during pregnancy or breastfeeding – inform your doctor immediately if you become pregnant while on phentermine.

Inform your doctor if you have any medical conditions (e.g. heart condition, high blood pressure, history of seizures) or are taking other medications.

Inform doctor if taking psychotropic drugs

  • Updated on 10/4/2017 12:00:00 AM
  • Article contributed by Pharmacy Department KK Women's and Children's Hospital
The information provided is not intended as medical advice. Terms of use. Information provided by SingHealth

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