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Compare Phentermine vs. Adderall

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

Key takeaways

Phentermine (Adipex-P) and Adderall (dextroamphetamine/amphetamine salts) are both stimulant medications, but they are used for different purposes. Phentermine is a sympathomimetic used for short-term weight management in adults with a high body mass index (BMI), while Adderall is used to treat attention deficit-hyperactivity disorder (ADHD) and narcolepsy. Phentermine is typically taken once daily, whereas Adderall can be taken multiple times a day. Both medications are available as a lower-cost generic and are controlled substances due to their risk to lead to misuse and dependence. Common phentermine side effects include dry mouth and trouble sleeping, while Adderall can cause loss of appetite and trouble sleeping. Both medications can raise blood pressure and heart rate. Avoid alcohol with both medications and be sure your prescriber and pharmacist have a complete list of your medications.

  • Phentermine (Adipex-P)
    Adderall
  • Phentermine (Adipex-P)
    Adderall

  • Summary of Phentermine vs. Adderall

    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.

    Summary for Stimulant
    Prescription only

    Adderall is a stimulant medication that's used to treat attention deficit-hyperactivity disorder (ADHD) and narcolepsy in adults and children. It contains the instant-release (IR) forms of dextroamphetamine and amphetamine salts. Adderall is available as a brand-name and lower-cost generic tablet that's taken by mouth. Your psychiatrist will adjust the dosage for you based on how well the medication works for you. Common side effects include trouble sleeping and loss of appetite.

  • Indications of Phentermine vs. Adderall

    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)
    Indications for
    •Attention deficit-hyperactivity disorder (ADHD)
    •Narcolepsy (daytime sleepiness)

  • Pros and Cons of Phentermine vs. Adderall

    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
    Pros and Const for Stimulant
    Pros
    •First-choice option for ADHD in children and adults
    •Starts working within an hour after taking
    •Available as a lower-cost generic
    •Can use together with behavioral counseling or other non-medication therapies to treat ADHD
    Cons
    •Has a risk of misuse and dependency
    •A controlled medication, so there are special requirements for getting the prescription filled
    •Dose needs to be raised and lowered slowly to avoid side effects and withdrawal symptoms
    •Not available as a liquid or patch form (unlike methylphenidate (Ritalin))

  • Common Side Effects of Phentermine vs. Adderall

    Common Side Effects for
    •Dry mouth
    •Headache
    •Tremor
    •Constipation
    •Diarrhea
    •High blood pressure
    •Fast heart rate
    •Difficulty sleeping
    Common Side Effects for
    •Upset stomach
    •Lower appetite
    •Weight loss
    •Nervousness
    •Changes in mood
    •Trouble sleeping

  • Warnings of Phentermine vs. Adderall

    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
    Common Side Effects for
    •Misuse and addiction
    •Dependence and withdrawal
    •Serious heart problems
    •Aggressive behavior and psychosis
    •Slowed growth in children
    •Seizures
    •Blood circulation problems (such as Raynaud's phenomenon)
    •Serotonin syndrome
    •Drug interactions

  • Prices with our coupons for Phentermine vs. Adderall

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