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Compare Diethylpropion vs. Phentermine

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

Key takeaways

Diethylpropion and phentermine (Adipex-P) are both sympathomimetic medications used for weight management in people with obesity. They work by suppressing appetite and are intended for short-term use. Diethylpropion is available as immediate-release and extended-release tablets, while phentermine comes in tablets, capsules, and orally disintegrating tablets. Diethylpropion is typically taken three times a day or once daily in the extended-release form, whereas phentermine is usually taken once daily, but can be taken twice daily depending on the form. Both medications are controlled substances due to their potential for misuse and dependence. Common side effects of diethylpropion include nausea, dry mouth, and trouble sleeping, while phentermine may cause dry mouth, headache, and constipation. Both medications should not be combined with other weight loss medications or taken within 14 days of monoamine oxidase inhibitors (MAOIs). Diethylpropion is not recommended for people over 65 or those with heart or kidney problems, while phentermine should be avoided in people with serious heart issues.

  • Diethylpropion
    Phentermine (Adipex-P)
  • Diethylpropion
    Phentermine (Adipex-P)

  • Summary of Diethylpropion vs. Phentermine

    Summary for Sympathomimetic amine
    Prescription only

    Diethylpropion is a medication that's taken by mouth help with obesity and weight loss. It's typically used together with a low-calorie diet and exercise plan. This medication is only meant to be used for a short period of time because it has many potential risks.

    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 Diethylpropion vs. Phentermine

    Indications for
    •Weight management when diet and exercise alone aren't enough in people with obesity
    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 Diethylpropion vs. Phentermine

    Pros and Const for Sympathomimetic amine
    Pros
    •An option to help manage your weight when diet and exercise alone haven't worked
    •Helps lower your appetite so you're not as hungry before meals
    •Comes as both an immediate-release tablet (taken before each meal) and an extended-release tablet (taken once a day)
    •Lower-cost generic available
    Cons
    •Might not be a good choice for people age 65 or older, or people with kidney or heart problems
    •Can cause withdrawal symptoms if you stop the medication after taking it for a while
    •Not for long-term use
    •Might not work as well as other weight loss medications
    •Not recommended for people who've taken similar weight loss medications (like phentermine (Adipex-P)) in the past year
    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 Diethylpropion vs. Phentermine

    Common Side Effects for
    •Nausea
    •Vomiting
    •Diarrhea
    •Upset stomach
    •Constipation
    •Dry mouth
    •Headache
    •Nervousness
    •Jitteriness
    •Racing heart
    •Trouble falling asleep
    •Changes in sex drive
    Common Side Effects for
    •Dry mouth
    •Headache
    •Tremor
    •Constipation
    •Diarrhea
    •High blood pressure
    •Fast heart rate
    •Difficulty sleeping

  • Warnings of Diethylpropion vs. Phentermine

    Common Side Effects for
    •High blood pressure affecting the heart and lungs
    •Heart valve problems
    •Potential for misuse and dependence
    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 Diethylpropion vs. Phentermine

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