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Compare Qsymia vs. Wegovy

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

Key takeaways

Qsymia (phentermine/topiramate) and Wegovy (semaglutide) are both medications used for weight loss in adults and children aged 12 and older. However, they have some important differences. Qsymia is a combination of a sympathomimetic and an antiepileptic, while Wegovy is a GLP-1 agonist. Qsymia is taken orally once a day, whereas Wegovy is injected under the skin once a week. Qsymia is a controlled substance because it contains phentermine, while Wegovy is not a controlled substance. Common side effects of Qsymia include dry mouth and constipation, while Wegovy often causes nausea and diarrhea. Qsymia can cause a fast heart beat, while Wegovy can increase the risk of some types of thyroid cancers. Both medications can cause problems with vision.

Qsymia (phentermine / topiramate ER)
Wegovy (semaglutide)
Qsymia (phentermine / topiramate ER)
Wegovy (semaglutide)
Summary of Qsymia vs. Wegovy
Summary for Sympathomimetic / Antiepileptic
Prescription only
Qsymia (phentermine / topiramate extended release) is a combination medication used to help with weight loss. It's approved for people over 12 who are considered obese and for some adults who are considered overweight. This medication is a tablet that you take once a day. You should also eat a balanced diet and exercise regularly for best results. Side effects include a "pins-and-needles" feeling, dry mouth, and constipation. You can only get this medication through the Qsymia REMS (Risk Evaluation and Mitigation Strategies) program because of the risk of birth defects if taken during pregnancy.
Summary for GLP-1 agonist
Prescription only
Wegovy (semaglutide) is a glucagon-like peptide-1 (GLP-1) receptor agonist. It comes in prefilled pens you use to inject the medication under the skin once a week. Wegovy (semaglutide) also comes as tablets that are swallowed once a day. This medication is approved for weight loss in some people. It can help lower the risk of heart attack, stroke, and death due to heart problems in adults with a larger body size and heart disease. The pens are also approved for certain adults with a liver problem called metabolic dysfunction-associated steatohepatitis (MASH). The medication works best when taken with a lower-calorie diet and regular exercise. Side effects include nausea, diarrhea, and stomach pain.
Indications of Qsymia vs. Wegovy
Indications for

•Weight loss and long-term weight management, together with diet and exercise, for certain people:

•People age 12 years and older considered obese

•Adults considered overweight with at least one weight-related condition (e.g., heart disease, high blood pressure, Type 2 diabetes)

Indications for
Injectable pens:

•
Weight loss and long-term weight management in:

•People ages 12 years and older who are considered obese

•Adults considered overweight with at least one weight-related condition (e.g., high blood pressure, Type 2 diabetes, high cholesterol)

•
Lowering the risk of heart attack, stroke, and death due to heart problems in adults with a larger body size and heart disease

•
Metabolic dysfunction-associated steatohepatitis (MASH) in adults with moderate-to-advanced liver scarring, but not cirrhosis

Tablets:

•Weight loss and long-term weight management in adults who are considered obese or overweight with at least one weight-related condition

•Lowering the risk of heart attack, stroke, and death due to heart problems in adults with a larger body size and heart disease
Pros and Cons of Qsymia vs. Wegovy
Pros and Const for Sympathomimetic / Antiepileptic
Pros

•A pill that's taken once a day

•Combines two ingredients that help lower appetite into one pill for convenience

•An option for certain children 12 years and older, if diet and exercise aren't enough

Cons

•Can raise the risk of depression or thoughts of self-harm

•Controlled substance and only available through a REMS program

•Not safe during pregnancy

Pros and Const for GLP-1 agonist
Pros

•Available as once-weekly injectable pens and as once-daily pills

•Injectable pens approved for weight loss in children ages 12 years and older considered obese

Cons

•Can cause stomach pain, nausea, and diarrhea

•Can't take with other semaglutide products (Ozempic, Rybelsus) or with other GLP-1 agonists
Common Side Effects of Qsymia vs. Wegovy
Common Side Effects for
Adults:

•Feeling of pins and needles (up to 20%)

•Dry mouth (up to 19%)

•Constipation (up to 16%)

•Upper respiratory tract infection (up to 16%)

•Headache (up to 11%)

•Change in taste (up to 9%)

•Trouble sleeping (up to 9%)

•Dizziness (up to 9%)

Children:

•Depression (up to 4%)

•Nausea (up to 4%)

•Fever (up to 4%)

•Dizziness (up to 4%)

•Joint pain (up to 4%)

Common Side Effects for

•Nausea (44%)

•Diarrhea (30%)

•Vomiting (24%)

•Constipation (24%)

•Stomach pain (20%)

•Headache (14%)

•Tiredness (11%)
Warnings of Qsymia vs. Wegovy
Common Side Effects for

•Harm to an unborn baby

•Mood problems and suicidal thoughts or behavior

•Fast heart beat

•Vision problems

•Problems concentrating

•Higher level of acid in blood (metabolic acidosis)

•Possible lower kidney function

•Kidney stones

•High body temperature and inability to sweat

•Serious allergic reactions and skin reactions

•Possible slowed growth in children

Common Side Effects for

•Possible risk for thyroid cancer

•Inflammation of the pancreas (pancreatitis)

•Gallbladder problems

•Low blood sugar

•Kidney damage

•Allergic reactions

•Eye problems in people with Type 2 diabetes (diabetic retinopathy)

•Faster heart rate

•Possible risk of self-harm

•Lung problems during general anesthesia or deep sedation
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Key takeaways

Summary of Qsymia vs. Wegovy

Indications of Qsymia vs. Wegovy

Pros and Cons of Qsymia vs. Wegovy

Common Side Effects of Qsymia vs. Wegovy

Warnings of Qsymia vs. Wegovy

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