Qsymia for Weight Loss

Qsymia diet pill

Qsymia (phentermine and topiramate) is one of several weight loss medications approved by the Federal Drug Administration (FDA). Before you talk to your doctor about a prescription, learn the research behind Qsymia to make an informed decision. Together with your doctor, you can decide whether this medication is the right choice for you.

Qsymia may help with weight loss, but there are additional side effects to consider before starting this medication. Here are a few things to think about.

What is Qsymia?

Qsymia is a combination of two drugs: phentermine and topiramate. Phentermine was originally used as part of the popular phen-fen drug combination, fenfluramine. Due to safety concerns, fenfluramine was eventually taken off the market. The formulation of Qsymia is different from the phentermine-based prescriptions that were used in the past.

Topiramate is a drug that has been traditionally used for the treatment of epilepsy and migraines. Qsymia combines phentermine and topiramate to suppress appetite and reduce food intake. This combination of substances has been proven to promote weight loss.

Qsymia may be prescribed for adults who have a body mass index (BMI) over 30. If you have a BMI of 27 or higher, along with a weight-related condition (such as type 2 diabetes or high blood pressure), your doctor may also recommend Qsymia.

People who are prescribed Qsymia are still expected to follow a healthy eating and exercise program in order to gain the full benefits of taking it.

How Qsymia Works

The exact mechanisms of action are not entirely understood, but some research suggests that it may affect neurotransmitter levels in the brain. Qsymia works to control hunger and craving, which may help people to lose weight.

Researchers believe Qsymia affects the hormone norepinephrine and gamma-aminobutyric acid, and glutamate to induce appetite suppression.


In published clinical trials, patients who took a lower dose of Qsymia (3.75mg phentermine/23mg topiramate) lost an average of 6.7% of their weight.

On the higher recommended dose (7.5mg phentermine/46mg topiramate), patients lost an average of 8.9% of their total body weight. Higher doses of Qsymia, up to 15mg phentermine/92mg topiramate, are also available.

Studies performed on overweight and obese adults have shown that Qsymia can produce lasting health benefits and greater weight loss in groups taking the medication when compared with the placebo group.

Average Weight Loss

If you are thinking about taking Qsymia, you can use this information to estimate your potential weight loss range. For example, based on clinical results, a patient who weighs 250 pounds could reasonably expect to lose 17 to 22 pounds of their starting body weight.

Individual results will vary, but the benefits of this medication rely on congruent lifestyle modifications, especially to achieve long-term success with weight loss.

Patients who take Qsymia should be monitored regularly by their physician. If you don't lose at least 3% of your body weight within the first 12 weeks, your doctor may advise you to discontinue the drug or take a higher dose.

If you do not lose at least 5% of your weight after moving to a higher dose, it's recommended to stop taking the pill gradually.


Studies looking at the potential cardiovascular risks of taking Qsymia show no increased risks for current users. Still, there need to be more studies to conclude whether new users could be at a greater risk.

Qsymia can possibly cause addiction and adverse cognitive effects such as attention, language, and memory impairment. The long-term effects of this drug are relatively unknown. With any weight loss medication, it is crucial to tailor it to individuals' health conditions and current status. It is essential to weigh the pros and cons of any weight loss medication.

Studies have shown an increased risk of cleft palate development in babies born to women taking topiramate during their first trimester. For this reason, it is advised that women of childbearing age take a monthly pregnancy test while on Qsymia.

Women must know immediately if they become pregnant while on Qsymia, as this knowledge provides the opportunity to stop taking the drug before congenital disabilities occur.

Patients are advised to receive regular heart-rate monitoring while on Qsymia. Qsymia is not recommended in people with cardiac issues or cerebrovascular disease. If you take medications for diabetes, high blood pressure, or anxiety, your doctor may need to adjust your dosage.

It can be dangerous to stop taking Qsymia abruptly, especially if you are on a higher dose. Some people do not respond to the effects of Qsymia at any dose and should not continue taking it if it doesn't work for them.

Qsymia Side Effects

Qsymia has potential side effects that people should be aware of before they begin taking it. 

  • Mood changes
  • Suicidal thoughts
  • Fear and anxiety
  • Panic attacks
  • Agitation, irritability, aggressiveness
  • Trouble sleeping
  • Kidney stones
  • Eye problems such as decreased vision, eye pain, fluid blockage
  • Fever
  • Numbness or tingling in hands and feet
  • Constipation
  • Dry mouth
  • Decreased sweating despite increased body temperature
  • Seizures (if the medication is stopped too suddenly)

It's a good idea to read through the complete drug information guide that should be provided to you by your doctor or pharmacist before you begin taking the Qsymia.

How Much Does Qsymia Cost?

The total price of Qsymia depends on the pharmacy and a few other factors. Several pharmacies sell a month’s supply of Qsymia at prices ranging from $180–$220, but your actual cost may depend on the dose that your physician prescribes. Taking the lower dose of medication is generally less expensive, averaging $120 per month wholesale.

Your insurance company may pay partially or in full for the medication. Since plans vary and change, check with your carrier to see if it is covered on your current plan. The makers of Qsymia also offer coupons to help you manage the cost of the diet pill if insurance doesn't cover the prescription. 

If you're a woman who can get pregnant, be sure to factor in the cost of a monthly pregnancy test when tallying the total cost. You can also talk to your doctor about a plan for having testing done as part of your office visits.

If you choose to invest in Qsymia, be aware that only certain pharmacies may dispense the drug. As part of an agreement with the FDA, drugmaker Vivus agreed to sell the medication only through pharmacies that take part in an educational program that ensures patients receive risk reduction information along with their medication.

Who Should Take Qsymia?

Qsymia should not be taken by people who only have a few pounds to lose. If you meet the BMI criteria and have tried other weight loss methods without success, Qsymia may be able to help.

If you're a woman planning to have children in the future, take extra caution before deciding to start Qsymia. If you are on medications for other health conditions, you should also be mindful of possible interactions.

Adjust your dosages per your doctor's recommendations, and stay up-to-date on follow-up visits to monitor your body's response to Qsymia.

Frequently Asked Questions

 What Should I Eat While Taking Qsymia?

Qsymia works best when combined with a reduced-calorie diet. Consume a diet consisting of plenty of fruits and vegetables, whole grains, lean protein, and healthy fats.

How Long Can You Take Qsymia?

You should take Qsymia for as long as your health care provider has prescribed. If you experience side effects, be sure to speak to your doctor to see if stopping the medication is best. Do not stop taking the medication on your own without consulting your doctor, as it can cause adverse side effects.

How Long Does it Take for Qsymia to Work?

Qsymia starts to work immediately after you take it to reduce hunger and cravings.

A Word From Verywell

Talk to your doctor about the potential health benefits of losing weight with Qsymia. Discussing your specific medical history and future plans will help you make the best decision with your provider.

It's important to remember that no pill can take the place of a healthy lifestyle. Not every medication works the same way for everyone. Monitoring your progress with your doctor will help you stay safe and avoid negative side effects.

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Article Sources
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