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Phentermine Patient Tips

How it works

Experts aren't sure exactly how phentermine works to encourage weight loss but believe it has appetite suppressant effects as well as other effects on the brain or metabolism.

Upsides

Used short-term as an aid to weight-loss in addition to exercise, behavioral modification and caloric restriction. Recommended only for people with an initial BMI of equal or more than 30 kg/m2, or 27 kg/m2 with risk factors for a cardiovascular event (such as controlled high blood pressure, diabetes, or high cholesterol).

Downsides

If you are between the ages of 18 and 60, take no other medication or have no other medical conditions, side effects you are more likely to experience include:

  • Risk of dependence and abuse. Abrupt cessation following prolonged dosing may cause a withdrawal effect (symptoms include extreme fatigue and depression).
  • May impair judgement and affect ability to drive or operate machinery.
  • Tolerance may develop to weight-loss effects. Do not increase dosage; drug may need to be discontinued under medical advice.
  • May cause high blood pressure and other adverse cardiovascular effects. Restlessness, insomnia, headache, psychosis, dry mouth, rash, sexual dysfunction, unpleasant taste and gastrointestinal disturbances have also been reported.
  • Should not be used in children aged 16 or less.

Notes: In general, seniors or children, people with certain medical conditions (such as liver or kidney problems, heart disease, diabetes, seizures) or people who take other medications are more at risk of developing a wider range of side effects. For a complete list of all side effects, click here.

Bottom Line

Phentermine is used for weight loss; however, use is limited by dependence and development of tolerance.

Tips

  • Administer before breakfast or one-to-two hours after breakfast. Avoid late evening administration as this may cause insomnia.
  • Dosage must be tailored to different individuals. Take exactly as directed and for the duration intended. If you find yourself gaining weight while taking phentermine see your doctor.
  • Should be used in addition to exercise, behavioral modification and caloric restriction.
  • Do not drive or operate machinery if this medicine impairs your judgement. Avoid alcohol
  • Should not be used at the same time as other medications used for weight loss.
  • Recommended only for people with an initial BMI of equal or more than 30 kg/m2, or 27 kg/m2 with risk factors for a cardiovascular event (such as controlled high blood pressure, diabetes, or high cholesterol).
  • Report any new shortness of breath, angina pain, fluid retention in legs or feet, or decrease in ability to exercise with no apparent cause to your doctor immediately.

Response and Effectiveness

Peak concentrations reached within in three to four hours. Magnitude of weight loss over taking no tablets amounts to less than a pound per week. Rate of weight loss is greatest in first few weeks of therapy.

References

Phentermine [package insert]. Revised 06/2015. LEADING PHARMA, LLC. https://www.drugs.com/pro/phentermine.html Accessed 02/2016

  • Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use phentermine only for the indication prescribed.

  • Disclaimer: Every effort has been made to ensure that this information is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. This drug information does not endorse drugs, diagnose patients or recommend therapy. It is an informational resource designed 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. Drugs.com does not assume any responsibility for any aspect of healthcare administered with the aid of this information. 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 1996-2017 Drugs.com. Revision Date: 2016-02-22 00:00:00

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