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Compare Phendimetrazine vs. Phentermine

Head-to-head comparisons of medication uses, side effects, warnings, and more.

Key takeaways

Phendimetrazine and phentermine (Adipex-P) are both sympathomimetic medications used for short-term weight management in adults with a body mass index (BMI) of 30 kg/m² or greater, or 27 kg/m² with other risk factors like high blood pressure. Both medications are controlled substances and appetite suppressants meant to be used alongside diet and exercise. However, they differ in several ways. Phendimetrazine is available as immediate-release tablets and extended-release capsules and is taken 1 to 3 times daily, depeneding on the formulation. In contrast, phentermine is available in tablets, capsules, and orally disintegrating tablets and is typically taken once daily. Possible side effects of both medications include high blood pressure and heart rate, restlessness, and trouble sleeping. Both medications should not be combined with other weight loss medications or taken with MAOIs like selegiline (Zelapar).

  • Phendimetrazine
    Phentermine (Adipex-P)
  • Phendimetrazine
    Phentermine (Adipex-P)

  • Summary of Phendimetrazine vs. Phentermine

    Summary for Sympathomimetic amine
    Prescription only

    Phendimetrazine, formerly known as brand-name medication Bontril, is a prescription sympathomimetic medication typically used in combination with diet and exercise. It works as an appetite suppressant in the brain to help adults with weight loss. It's available as an immediate-release tablet taken by mouth two to three times per day, and an extended-release capsule taken once per day. Side effects include restlessness, headache, and high blood pressure.

    Summary for Sympathomimetic
    Prescription only

    Phentermine (Adipex-P) is an appetite suppressant. It's a prescription weight loss pill for people ages 17 years and older. This medication works best when it's part of a treatment plan that involves healthy diet and regular exercise. Phentermine (Adipex-P) is taken by mouth once daily, typically in the morning. Some of the more common side effects of this medication include dry mouth, trouble sleeping, and headache.

  • Indications of Phendimetrazine vs. Phentermine

    Indications for

    Short-term treatment for weight management in adults with a body mass index (BMI) of:

    •30 kg/m2 or greater; or
    •27 kg/m2 or greater with other risk factors (e.g., high blood pressure, high blood sugar, high cholesterol)
    Indications for

    Short-term treatment for weight management in adults with a body mass index (BMI) of:

    •30 kg/m2 or greater; or
    •27 kg/m2 or greater, and with at least one other weight-related condition (e.g., high blood pressure, high blood sugar, high cholesterol)

  • Pros and Cons of Phendimetrazine vs. Phentermine

    Pros and Const for Sympathomimetic amine
    Pros
    •Comes in immediate-release and extended-release forms
    •Available as a lower-cost generic form
    Cons
    •Risk of misuse and dependency
    •Typically recommended to be used for a short period of time (a few weeks)
    Pros and Const for Sympathomimetic
    Pros
    •Can help you lose 5% to 10% of body weight
    •Usually taken by mouth once per day
    •Available as a lower-cost generic
    •Comes as tablets, capsules, and orally disintegrating tablets
    Cons
    •Most insurance companies don't cover the cost of phentermine (Adipex-P).
    •Has a risk of misuse and dependence since it's a stimulant medication that's similar to amphetamines
    •Might not be a good choice for people with high blood pressure
    •Should be avoided in children 16 years of age and younger, pregnant and breastfeeding women, and people with serious heart problems

  • Common Side Effects of Phendimetrazine vs. Phentermine

    Common Side Effects for
    •Fast heartbeat
    •High blood pressure
    •Restlessness
    •Trouble sleeping
    •Nervousness
    •Shakiness
    •Sweating
    Common Side Effects for
    •Dry mouth
    •Headache
    •Tremor
    •Constipation
    •Diarrhea
    •High blood pressure
    •Fast heart rate
    •Difficulty sleeping

  • Warnings of Phendimetrazine vs. Phentermine

    Common Side Effects for
    •Not safe with other weight loss medications
    •Lower response to the medication over time
    •Risk of misuse and dependence
    •High blood pressure in the lungs (pulmonary hypertension)
    •Heart valve problem
    •Risk of high blood pressure
    •Risk of low blood sugar in people with diabetes
    Common Side Effects for
    •Not safe to combined with other weight loss medications
    •Phentermine not working well
    •Risk of misuse and dependence
    •Trouble concentrating or problem with coordination
    •Heart and lung problems
    •Risk of high blood pressure
    •Risk of low blood sugar in people with diabetes

  • Prices with our coupons for Phendimetrazine vs. Phentermine

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