The ranking, by trial results
The strongest prescription weight-loss pill right now is the Wegovy pill (oral semaglutide 25 mg), based on average loss in its main trial. Qsymia comes next.
| Pill | What it is | Average loss in main trials | Good to know |
|---|---|---|---|
| Wegovy pill 25 mg | Daily GLP-1 tablet (oral semaglutide) | about 13.6% vs 2.2% on placebo (64 weeks) | Taken on an empty stomach with a sip of water |
| Qsymia | Phentermine plus extended-release topiramate | roughly 9% to 11% at the top dose vs about 1% to 2% (about 1 year) | Strict pregnancy precautions because of birth defect risk |
| Contrave | Naltrexone plus bupropion | about 5% to 6% vs about 1% to 2% (about 1 year) | Boxed warning about suicidal thoughts |
| Orlistat | Blocks some fat absorption (Xenical 120 mg; Alli 60 mg over the counter) | a few percent more than placebo | Oily, urgent stools if meals are high in fat |
| Phentermine | Appetite suppressant | Approved for short-term use | Controlled substance; raises heart rate and blood pressure |
Figures are rounded from FDA labels and the main trials, as of our last review. Trials differ, so treat this as a rough order, not an exact race.
Why the GLP-1 pill leads
Oral semaglutide is the same medicine as the Wegovy injection, made to survive the stomach. It quiets appetite and slows how fast your stomach empties, which is why its results look a lot like the shot. More: the Wegovy pill and Wegovy pill vs injection.
The catch is the routine: you take it first thing in the morning with no more than 4 ounces of water, then wait 30 minutes before eating or drinking anything else.
A pill to watch
Orforglipron is a GLP-1 pill from Eli Lilly that doesn't need the empty-stomach routine. In the ATTAIN-1 trial, people on the highest dose lost about 12.4% at 72 weeks. Lilly said it submitted it to the FDA; check FDA.gov or Lilly for whether it's approved yet.
Stronger isn't automatically better
- Side effects differ. GLP-1 pills cause mostly stomach effects. Qsymia can affect mood, sleep and concentration. Contrave can raise blood pressure.
- Health history matters. Some options aren't safe with certain heart, seizure, eye or mental health conditions.
- Cost and coverage vary. See the GLP-1 cost index.
Who each pill may not suit
Every label lists people who shouldn't take the medicine. Here are some of the main ones, as of our last review. Your prescriber will check the full list against your health history.
| Pill | Label says not for people who |
|---|---|
| Wegovy pill | Have a personal or family history of medullary thyroid carcinoma or MEN 2, or a serious allergy to semaglutide |
| Qsymia | Are pregnant, have glaucoma or an overactive thyroid, or took an MAOI antidepressant in the last 14 days |
| Contrave | Have uncontrolled high blood pressure, seizures, a past eating disorder such as bulimia or anorexia, or take opioids |
| Orlistat | Have chronic malabsorption or cholestasis, or are pregnant |
| Phentermine | Have heart disease, an overactive thyroid, glaucoma, a history of drug misuse, or are pregnant |
How you'll know if it's working
Some labels build in a check-in, so nobody stays on a pill that isn't helping:
- Qsymia: the label asks prescribers to check progress after 12 weeks on the recommended dose, and again after 12 weeks on the top dose.
- Contrave: the label says to stop if you haven't lost at least 5% of your starting weight after 12 weeks on the full dose.
- Wegovy pill: the dose steps up every 30 days for the first 90 days, so the full effect takes months to show.
A weekly weigh-in at the same time of day makes these check-ins easier. The weigh-in tracker smooths out the normal day-to-day ups and downs. Small wins count, so note how your clothes fit and how you feel too.
Questions to ask your prescriber
- Based on my health history, which pills are safe options for me?
- How much weight loss is realistic, and by when should we check?
- Which side effects should I expect, and which mean I should call you?
- Does it interact with anything I already take, including supplements?
- Is a pill or a weekly shot a better fit for my routine and my coverage?
Writing your questions down before the visit helps. Bring a list of every medicine and supplement you take.
When to talk to your doctor
- Before starting any weight-loss pill, including over-the-counter orlistat.
- If you could become pregnant and are considering Qsymia.
- If you notice mood changes or thoughts of self-harm on any of these medicines.
- If you have a fast heartbeat, chest pain or very high blood pressure.
Run your numbers
Keep reading
Common questions
What is the strongest prescription weight loss pill?
Based on trial averages, the Wegovy pill (oral semaglutide 25 mg), at about 13.6% loss over 64 weeks. Qsymia is next.
Is phentermine the strongest diet pill?
No. Phentermine is approved only for short-term use, and combination or GLP-1 pills produced more loss in longer trials.
Is there a strong weight loss pill over the counter?
The only FDA-approved over-the-counter option is orlistat 60 mg (Alli), and its effect is modest.
Sources
- Wegovy pill prescribing information (FDA label on DailyMed)
- Qsymia prescribing information (FDA label on DailyMed)
- Contrave prescribing information (FDA label on DailyMed)
- Orlistat prescribing information (FDA label on DailyMed)
- Phentermine prescribing information (FDA label on DailyMed)
- NIDDK: prescription medications to treat overweight and obesity
- Eli Lilly news releases (orforglipron)
Clinician review pending. Drafted from primary sources and waiting for sign-off by a licensed clinician (MD, DO or PharmD) before launch. Every number is checked against its source. Drug facts are re-checked quarterly, prices monthly and whenever a label changes. How we review · Report an error