FDA approved in 2012, Qsymia (phentermine and topiramate) is an extended-release prescription medication that promises to deliver around-the-clock hunger and craving control, helping some adults lose weight and keep it off.
Additionally, when used in conjunction with a reduced calorie diet and increased physical activity, the drug has been clinically shown to help patients lose weight three times faster than diet and exercise alone. On average, among more than 3,700 trial participants, they also experienced:
- After 12 weeks: 15 - 19 lbs lost, 2 - 3” off waist
- After 28 weeks: 22 - 29 lbs lost, 3 - 4" off waist
- After 56 weeks: 24 - 32 lbs lost, 4 - 5” off waist
Together, this is why VIVUS, Inc tells us that Qsymia has helped more than half a million patients achieve their weight loss goals. Does this mean it's the best option for you, though? Over the next few minutes, this is the primary question we'll focus on.
How Do Qsymia’s Ingredients Work?
The manufacturer is upfront when stating on their website: “The precise mechanism of action for the two ingredients in Qsymia that contribute to chronic weight management is not fully understood.”
With this caveat in mind, they go on to explain that it’s thought phentermine immediately works to reduce appetite, while topiramate’s extended-release functionality may increase the feeling of fullness, or affect certain parts of the brain that cause certain foods to taste differently. In turn, this might reduce eating-related pleasure.
According to the Qsymia website, a typical treatment regimen might look something like this (remember, yours could differ based on your doctor’s diagnosis):
- First two weeks – Take one 3.75 mg/23 mg capsule each morning as a starter dose. You may not lose weight during this phase.
- Weeks three through 12 – Take one 7.5 mg/46 mg capsule each morning as a recommended dose. If you achieve 3% weight loss or greater, you’ll remain at this dose.
- Weeks 13 through 15 – If the recommended dose doesn’t deliver at least 3% weight loss, your doctor may escalate your daily dosage to 11.25 mg/69 mg for two weeks (called a titration dose).
- Weeks 16+ – Finally, you’ll continue with 15 mg/92 mg daily doses (referred to as ‘high’ doses), as prescribed by your healthcare provider.
Patients will also have no-cost access to the ‘Q and Me’ support resource, which the manufacturer tells us provides helpful information that can keep you motivated and help you lose weight “sensibly, healthily, [and] effectively by encouraging proper nutrition and increased physical activity.”
What are Some Potential Qsymia Side Effects?
While your doctor will provide a full diagnosis of your condition, the manufacturer points out that Qsymia is intended “for chronic weight management in adults with an initial body mass index (BMI) of”:
- 30 kg/m2 or greater (obese) or
- 27 kg/m2 or greater (overweight) in the presence of at least one weight-related medical condition such as high blood pressure, type 2 diabetes, or high cholesterol
Even if you meet these criteria, they emphasize the drug shouldn't be taken by those who are pregnant or who plan on becoming pregnant, due to an increased risk of birth defects (specifically, cleft palate). You also shouldn’t take it if you have glaucoma or hyperthyroidism, or are taking MAOI medications.
Common side effects (no dosages or other specifics noted) include “numbness or tingling in the hands, arms, feet, or face (paraesthesia); dizziness; changes in the way foods taste or loss of taste (dysgeusia); trouble sleeping (insomnia); constipation; and dry mouth.”
Less common side effects referenced include increased heart rate, suicidal thoughts or actions, serious eye problems, mood changes and trouble sleeping, concentration, memory, and speech difficulties; metabolic acidosis, hypoglycemia, kidney stones, and decreased sweating and increased body temperature (fever).
You’ll obviously need to have an in-depth discussion with your doctor to obtain a Qsymia prescription, at which point they can advise of any potential side effects or medication interactions based on your specific diagnosis.
How Much Does Qsymia Cost?
Like any prescription medication, exactly what you’ll pay for Qsymia can depend on a variety of factors, including the pharmacy you buy from and whether or not it’s covered (and to what extent) by your health insurance plan.
With this said, GoodRx lists the average retail price of a 30-day supply at $234.93.
VIVUS offers the ability to obtain a free two-week starter dose or save up to $95 on your first 30-day prescription, regardless of dose, by signing up for the Qsymia Savings Card. Afterward, you can save up to $65 per monthly prescription for up to 36 months.
The Details Surrounding Qsymia Patient Reviews
The FDA approved Qsymia in 2012, so we encountered quite a bit of online feedback at the time of our research.
Between Drugs.com and WebMD, we found more than 580 combined patient reviews, who had given Qsymia a combined average rating of about 3.5 stars.
Many complimented its helpfulness for reducing cravings and improving weight loss, although common complaints cited high price without insurance coverage, and no improvement in cravings or pounds lost. Side effects included dry mouth, headache, delayed memory recall, and tingling in the feet or face.
Are There Other Prescription Weight Loss Medications Like Qsymia?
There are a handful of prescription medications currently on the market that promise to help individuals lose about the same amount of weight as Qsymia. In fact, more than one includes some of the same ingredients, but at meaningfully lower prices:
According to a 2016 LA Times article reporting a comparison between Qsymia, Saxenda, Contrave, and Alli:
"Qsymia fared best in promoting the loss of 5% of body weight in patients taking it. A median of 75% of those taking Qsymia lost 5% of their body weight, while a median of 63% of participants taking Saxenda and 55% of those taking Contrave did.
A median of 49% of participants taking Belviq and 44% of those taking the over-the-counter medication Alli succeeded in losing 5% of their body weight in the trials. A median of 23% of those on a placebo pill lost 5% of their weight.”
With this in mind, which medication will work best for you? And will you necessarily achieve better results by paying a higher price?
The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) emphasizes that “Weight-loss medications are meant to help people who may have health problems related to overweight or obesity.” In other words, if you’re simply looking to shed a few ‘vanity pounds,’ you shouldn’t consider them an option.
Since obesity is primarily defined by body-mass index (BMI), they explain that the best candidates for prescription weight loss medications are often those who with a BMI of 30 or more, or “a BMI of 27 or more and weight-related health problems, such as high blood pressure or type 2 diabetes.” You’ll notice this is the same target demographic as Qsymia.
However, they also emphasize that these medications aren’t intended to replace physical activity or healthy eating habits. In fact, “studies show that weight-loss medications work best when combined with a lifestyle program.”
In the end, they emphasize that choosing a medication is a decision that can only be made between you and your doctor. If they recommend it, though, they point out you’ll only want to purchase from a doctor-approved pharmacy.
Will Qsymia Deliver Real-World Weight Loss Results?
Losing weight is an intensely personal process since what works fantastically for one person might be a total flop for another, and vice versa. Even the Qsymia website explains that just a few of the variable that might impact your results include "your BMI, diet, activity, dose of Qsymia, and other factors."
With this said, it seems that based on the results of two large, randomized, placebo-controlled clinical trials among 3,700+ participants, the medication delivered meaningfully better outcomes than those who didn't receive it. On top of this, side effects were uncommon and generally mild.
With these core details as your foundation, the next step should be to talk with your doctor about whether or not Qsymia—or any other prescription weight loss medication, for that matter—is appropriate, based on your diagnosis.
>> Read next: A Beginner’s Guide to Losing Weight and Getting in Shape