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Compare Qsymia vs. Mounjaro

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

Key takeaways

Qsymia (phentermine/topiramate) and Mounjaro (tirzepatide) are both medications used to help with weight management, but they have some important differences. Qsymia is a combination of phentermine, a sympathomimetic, and topiramate, an antiepileptic, and is FDA-approved for weight loss in people over 12 living with obesity or are living with overweight and have at least weight-related condition. Mounjaro is a GIP and GLP-1 agonist approved for improving blood sugar control in adults with Type 2 diabetes but is also sometimes used off-label for weight loss. Qsymia is taken orally once a day, while Mounjaro is injected under the skin once a week. Qsymia is a controlled substance due to the phentermine component, whereas Mounjaro is not. Common side effects of Qsymia include dry mouth and constipation, while Mounjaro often causes nausea and diarrhea. Qsymia can cause a fast heart beat, while Mounjaro can increase the risk of some types of thyroid cancers. Both medications can cause problems with vision.

Qsymia (phentermine / topiramate ER)
Mounjaro (tirzepatide)
Qsymia (phentermine / topiramate ER)
Mounjaro (tirzepatide)
Summary of Qsymia vs. Mounjaro
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 GIP and GLP-1 agonist
Prescription only
Mounjaro (tirzepatide) is a prescription injection used to improve blood sugar control in people 10 years and older with Type 2 diabetes. It works best when you also follow a nutritious diet and exercise regularly. Mounjaro (tirzepatide) belongs to the drug class called GIP and GLP-1 agonists. The dosage is convenient because it's injected under the skin once a week. Some common side effects of Mounjaro (tirzepatide) include nausea and diarrhea. It can also lower your appetite, which might lead to some weight loss.
Indications of Qsymia vs. Mounjaro
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

•Type 2 diabetes in adults and children 10 years of age and older
Pros and Cons of Qsymia vs. Mounjaro
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 GIP and GLP-1 agonist
Pros

•Given once weekly

•Can lower A1C by an average of up to 2.3% in about 9 months

•Has different forms some people can choose from (vials, single-dose injectable pens, multi-dose KwikPens)

•Can use if you have liver or kidney problems

Cons

•Must give as an injection given under the skin

•Can cause unpleasant side effects like nausea, vomiting, and diarrhea

•Takes time to reach a dose that works well

•Might not be safe during pregnancy
Common Side Effects of Qsymia vs. Mounjaro
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 (12-18%)

•Diarrhea (12-17%)

•Low appetite (5-11%)

•Vomiting (5-9%)

•Indigestion (5-8%)

•Constipation (6-7%)

•Stomach pain (5-6%)
Warnings of Qsymia vs. Mounjaro
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

•Risk of thyroid cancer

•Inflammation of the pancreas (pancreatitis)

•Low blood sugar (hypoglycemia) when used with other diabetes medications

•Allergic reactions

•Stomach side effects

•Kidney damage due to dehydration

•Eye problems in people with diabetic retinopathy

•Gallbladder problems

•Lung problems during general anesthesia or deep sedation

•Don't share Mounjaro KwikPens with anyone
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Key takeaways

Summary of Qsymia vs. Mounjaro

Indications of Qsymia vs. Mounjaro

Pros and Cons of Qsymia vs. Mounjaro

Common Side Effects of Qsymia vs. Mounjaro

Warnings of Qsymia vs. Mounjaro

Prices with our coupons for Qsymia vs. Mounjaro

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