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.
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).
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.
- 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.
Phentermine [package insert]. Revised 06/2015. LEADING PHARMA, LLC. https://www.drugs.com/pro/phentermine.html Accessed 02/2016
More about phentermine
- Side Effects
- During Pregnancy
- Dosage Information
- Drug Images
- Drug Interactions
- Support Group
- Pricing & Coupons
- En Español
- 2257 Reviews – Add your own review/rating
- Drug class: anorexiants
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- 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.
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