Belviq, Qsymia: New Weight Loss Drugs Compared
What You Need to Know About New Weight Loss Drugs Belviq and Qsymia
Who should and shouldn't take Belviq? Who should and shouldn't take Qsymia?
Belviq and Qsymia are approved for similar problems:
Pregnant women should not take either Belviq or Qsymia.
Qsymia has particular risks for pregnancy, as it can cause birth defects if taken in the first months of pregnancy, even before a woman knows she is pregnant. Women of childbearing age must use effective birth control to keep from becoming pregnant while taking Qsymia.
Qsymia should not be taken by:
- Pregnant women
- People with glaucoma
- People who have been told they have an overactive thyroid
- People taking a type of antidepressant called a MAOI
- People allergic to phentermine or topiramate
Belviq should not be taken by:
- Pregnant or nursing women
- People taking drugs linked to valvular heart disease, such as cabergoline (Dostinex)
Belviq should be taken with caution by:
- People taking certain medicines for depression; migraine; the common cold; or mood, anxiety, psychotic, or thought disorders
- Men with conditions that predispose them to erections lasting more than four hours. These conditions include sickle cell anemia, multiple myeloma, and leukemia
- Men with a deformed penis
Qsymia and Belviq each come with a long list of important safety information, but this list is different for each drug.
Qsymia approval required Vivus to set up a strict Risk Evaluation and Mitigation Strategy (REMS). This program includes a medication guide giving patients important safety information, prescriber training, and pharmacy certification.
Which works better, Belviq or Qsymia?
There's no way to know for sure. Qsymia and Belviq have never been tested in a head-to-head clinical trial.
In the placebo-controlled clinical trials that led to approval:
- People taking Belviq had an average weight loss that was 3% to 3.7% greater than people taking placebo.
- After taking Belviq for one or two years, some 47% of people without diabetes lost at least 5% of their body weight. Only 23% of patients taking an inactive placebo lost this much weight.
- People taking Qsymia for up to one year had an average weight loss of 8.9% over those taking an inactive placebo.
- 70% of people taking Qsymia lost at least 5% of their body weight. Only 20% of patients taking an inactive placebo lost this much weight.
These numbers cannot be used to compare the two drugs, as the clinical trials had different designs.
How long would I have to keep taking Qsymia or Belviq?
People are supposed to keep taking Qsymia or Belviq for the rest of their lives, unless they develop side effects or have other reasons to stop.