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Compare Phentermine vs. Ozempic

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

Key takeaways

Phentermine (Adipex-P) and semaglutide (Ozempic) are both medications used to help with weight management, but they belong to different drug classes and have important differences. Phentermine is a sympathomimetic stimulant primarily used for short-term weight loss in adults with a high body mass index (BMI), while semaglutide is a glucagon-like peptide-1 (GLP-1) agonist used to treat Type 2 diabetes and reduce the risk of heart problems in adults with diabetes. Ozempic is sometimes used off-label for weight loss. Phentermine is taken orally, usually once a day, and is available in various forms, including tablets and capsules. In contrast, semaglutide is an injection used under the skin once a week. Phentermine is a controlled substance due to its potential for misuse and dependence, whereas semaglutide is not. Common side effects of phentermine include dry mouth and trouble sleeping, while semaglutide often causes nausea and diarrhea. Additionally, phentermine is available as a lower-cost generic, whereas semaglutide is only available as a brand-name medication.

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

  • Summary of Phentermine vs. Ozempic

    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 GLP-1 agonist
    Prescription only

    Ozempic (semaglutide) is a prescription injection used with diet and exercise to help manage Type 2 diabetes in adults. It's also FDA approved to lower the risk of heart attack, stroke, and heart-related death in those with Type 2 diabetes and heart disease. In addition, it can reduce the risk of worsening kidney problems in people with Type 2 diabetes and chronic kidney disease (CKD). Ozempic (semaglutide) is a GLP-1 agonist that's injected under the skin once a week. Common side effects include nausea, vomiting, and diarrhea.

  • Indications of Phentermine vs. Ozempic

    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
    •Type 2 diabetes
    •Lower the risk of heart attack, stroke, and heart-related death in adults with Type 2 diabetes and heart disease
    •Lower the risk of worsening kidney problems and heart-related death in adults with Type 2 diabetes and chronic kidney disease (CKD)

  • Pros and Cons of Phentermine vs. Ozempic

    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 GLP-1 agonist
    Pros
    •Only given once per week
    •Might help you lose weight
    •Helps lower the risk of heart problems and kidney problems in people with type 2 diabetes
    •Can store open and used pens at room temperature for up to 8 weeks
    Cons
    •Is an injection given under the skin
    •Commonly causes nausea, vomiting, and diarrhea
    •Risk of low blood sugar if taken with certain diabetes medications
    •Can't be used for Type 1 diabetes

  • Common Side Effects of Phentermine vs. Ozempic

    Common Side Effects for
    •Dry mouth
    •Headache
    •Tremor
    •Constipation
    •Diarrhea
    •High blood pressure
    •Fast heart rate
    •Difficulty sleeping
    Common Side Effects for
    •Nausea (16-20%)
    •Diarrhea (9%)
    •Vomiting (5-9%)
    •Stomach pain (6-7%)
    •Constipation (3-5%)

  • Warnings of Phentermine vs. Ozempic

    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
    •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 problems
    •Severe allergic reactions
    •Gallbladder problems
    •Lung problems during anesthesia or deep sedation

  • Prices with our coupons for Phentermine vs. Ozempic

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