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Compare Benzphetamine vs. Phentermine

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

Key takeaways

Benzphetamine (Didrex) and phentermine (Adipex-P) are both sympathomimetic medications used for short-term weight management in adults. They work by suppressing appetite. Both medications are taken orally and are controlled substances due to their potential for misuse and dependence. However, there are several differences between them. Benzphetamine is a Schedule III medication, while phentermine is a Schedule IV medication, meaning phentermine may have a lower risk of misuse and dependence. Benzphetamine is available only as an oral tablet, whereas phentermine comes in various forms, including tablets, capsules, and orally disintegrating tablets. Phentermine is approved for use in individuals with a BMI of 27 kg/m² or greater with weight-related conditions, while benzphetamine is approved for those with a BMI of 30 kg/m² or greater. Both medications can cause a fast heart beat, restlessness, and high blood pressure and interact with monoamine oxidase inhibitors (MAOIs). Neither one should not be combined with other weight loss medications.

  • Benzphetamine
    Phentermine (Adipex-P)
  • Benzphetamine
    Phentermine (Adipex-P)

  • Summary of Benzphetamine vs. Phentermine

    Summary for Sympathomimetic amine
    Prescription only

    Benzphetamine, formerly known by its brand name Didrex, is a prescription appetite suppressant that's used with diet and exercise to help adults with weight loss. It's classified as a sympathomimetic medication and is also a Schedule III controlled substance. Benzphetamine is currently available only as a generic tablet that's taken by mouth once per day. Side effects include high blood pressure, trouble sleeping, and restlessness.

    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 Benzphetamine vs. Phentermine

    Indications for

    Short-term treatment for weight management in adults with a body mass index (BMI) of 30 kg/m2 or greater

    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 Benzphetamine vs. Phentermine

    Pros and Const for Sympathomimetic amine
    Pros
    •Taken by mouth once per day
    •Available as a lower-cost generic medication
    Cons
    •Risk of misuse and dependency
    •Doesn't have a lot of clinical evidence or experience
    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 Benzphetamine vs. Phentermine

    Common Side Effects for
    •Fast heartbeat
    •High blood pressure
    •Feeling overstimulated
    •Restlessness or shakiness
    •Dizziness
    •Trouble sleeping
    •Sweating
    Common Side Effects for
    •Dry mouth
    •Headache
    •Tremor
    •Constipation
    •Diarrhea
    •High blood pressure
    •Fast heart rate
    •Difficulty sleeping

  • Warnings of Benzphetamine 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 Benzphetamine vs. Phentermine

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