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Compare Rybelsus vs. Phentermine

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

Key takeaways

Rybelsus (semaglutide) and Adipex-P (phentermine) are both medications that can help people lose weight, but they belong to different medication classes and have distinct uses. Rybelsus is a glucagon-like peptide-1 (GLP-1) receptor agonist primarily FDA-approved for treating Type 2 diabetes, with weight loss being a potential off-label benefit. In contrast, Adipex-P is a sympathomimetic stimulant specifically FDA-approved for short-term weight management in adults with a high body mass index (BMI). Rybelsus is taken as an oral tablet once daily, while Adipex-P is also taken orally but can be dosed once or twice daily depending on the form. Rybelsus is only available as a brand-name medication, whereas Adipex-P is available as a lower-cost generic. Common side effects of Rybelsus include nausea, vomiting, and diarrhea, while Adipex-P may cause dry mouth and trouble sleeping. Rybelsus has a warning for thyroid cancer, and Adipex-P is a controlled substance and carries a risk of misuse and dependence. Additionally, Rybelsus can interact with other diabetes medications, and Adipex-P should not be combined with other weight loss medications.

  • Rybelsus (semaglutide)
    Phentermine (Adipex-P)
  • Rybelsus (semaglutide)
    Phentermine (Adipex-P)

  • Summary of Rybelsus vs. Phentermine

    Summary for GLP-1 agonist
    Prescription only

    Rybelsus (semaglutide) is a brand-name GLP-1 agonist that helps lower blood sugar in adults with Type 2 diabetes. It's also FDA approved to help reduce the risk of heart attack, stroke, and heart-related death in people with Type 2 diabetes who are at risk for these events. The medication comes as a pill that's taken by mouth once a day, at least 30 minutes before you eat, drink, or take any other medications by mouth. It’s used along with diet and exercise, and might also help with weight loss. Common side effects include nausea, stomach pain, and diarrhea.

    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 Rybelsus vs. Phentermine

    Indications for
    •Type 2 diabetes
    •Lower the risk of heart attack, stroke, and heart-related death in adults with Type 2 diabetes at high risk for these events
    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 Rybelsus vs. Phentermine

    Pros and Const for GLP-1 agonist
    Pros
    •Only needs to be taken once per day
    •First GLP-1 agonist in pill form
    •Helps lower blood sugar and might also support weight loss
    Cons
    •Must be taken on an empty stomach
    •Stomach side effects like nausea, diarrhea, and stomach pain are common
    •Can't be used for Type 1 diabetes
    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 Rybelsus vs. Phentermine

    Common Side Effects for
    •Nausea (11-20%)
    •Stomach pain (10-11%)
    •Diarrhea (9-10%)
    •Lower appetite (6-9%)
    •Vomiting (6-8%)
    •Constipation (5-6%)
    Common Side Effects for
    •Dry mouth
    •Headache
    •Tremor
    •Constipation
    •Diarrhea
    •High blood pressure
    •Fast heart rate
    •Difficulty sleeping

  • Warnings of Rybelsus vs. Phentermine

    Common Side Effects for
    •Risk of thyroid tumors
    •Inflammation of the pancreas (pancreatitis)
    •Eye problems
    •Low blood sugar (hypoglycemia) when taken with certain diabetes medications
    •Kidney damage
    •Severe stomach side effects
    •Severe allergic reactions
    •Gallbladder problems
    •Lung problems during anesthesia or deep sedation
    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 Rybelsus vs. Phentermine

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