Qsymia approved for patients aged 12 and older

The Food and Drug Administration approved a new use for Qsymia (phentermine and topiramate extended-release capsules) on June 27, 2022, allowing doctors to prescribe it to adolescents aged 12 and older for chronic weight management ^[1]. Qsymia had already been approved for adults in July 2012 ^[1]. Unlike Wegovy or Zepbound, Qsymia is not a GLP-1 medicine; it combines an appetite suppressant, phentermine, with an anti-seizure drug, topiramate ^[1].

The approval covers adolescents with a body mass index at or above the 95th percentile for their age and sex, the clinical definition of obesity in youth, who have not lost weight or kept it off through diet and exercise changes alone ^[1]. The FDA notes that about 21% of U.S. adolescents, or roughly 1 in 5, are considered obese, and that obesity in youth raises the risk of conditions like heart disease and often persists into adulthood ^[1].

The decision rests on a 56-week, placebo-controlled trial of 223 adolescents aged 12 to under 17 ^[1]. Participants took either Qsymia 7.5 mg/46 mg (54 people), Qsymia 15 mg/92 mg (113 people), or a placebo (56 people), all alongside counseling on reduced-calorie eating and more physical activity ^[1]. By the end of the study, the lower dose group lost an average of 4.8% of their BMI and the higher dose group lost 7.1%, while the placebo group gained an average of 3.3% of BMI ^[1]. The FDA says Qsymia's effect on heart disease or heart-related death has not been established, and it has not been studied in combination with other weight-loss products ^[1].

Qsymia carries a boxed-style set of warnings. Because it can cause birth defects, including cleft lip and cleft palate, if taken during pregnancy, it is available only through a restricted program called the Qsymia REMS, which requires a negative pregnancy test before starting, monthly pregnancy testing, and effective contraception for patients who can become pregnant ^[1]. The label also warns about increased heart rate, suicidal thoughts and behavior, slowed growth in adolescents, eye problems, mood and sleep changes, cognitive impairment, metabolic acidosis, and reduced kidney function ^[1]. In the pediatric trial, the most common side effects were depression, dizziness, joint pain, fever, flu, and ankle sprain ^[1]. In adults, common side effects include tingling sensations, dizziness, altered taste, insomnia, constipation, and dry mouth ^[1].

Why it matters for patients

For families weighing options for adolescent obesity, Qsymia's approval means a pill-based, non-GLP-1 alternative exists alongside injectable GLP-1 drugs like Wegovy, which received its own adolescent approval around the same period. Because Qsymia works differently than GLP-1 medicines, it comes with a distinct set of warnings, including the pregnancy-related restrictions managed through the REMS program, and the need to monitor growth in adolescents specifically ^[1]. The trial data show a real difference between doses and placebo, but the study also shows that without effective treatment, the placebo group's BMI rose during the same 56 weeks, underscoring how difficult weight management can be through lifestyle changes alone ^[1]. The FDA is explicit that unanswered questions remain, including whether Qsymia reduces heart disease risk or death, which matters for patients and families thinking about long-term treatment ^[1].

What happens next

The approval, granted to Vivus, LLC, followed standard FDA review ^[1]. The label directs prescribers to use Qsymia only as an addition to reduced-calorie diet and increased physical activity, not as a standalone treatment ^[1]. Longer-term safety and cardiovascular outcome data for adolescents are not detailed in this approval and are not yet known from the sources reviewed here.