Semaglutide vs Phentermine: Which One?
One is an older short-term stimulant, the other a newer long-term GLP-1. Here is the honest difference.
The short answer
Phentermine is an older, FDA-approved stimulant appetite suppressant intended for short-term use (typically a few weeks). Semaglutide is a GLP-1 medication intended for long-term chronic weight management. They work differently, suit different people, and a physician decides which fits.
Quick comparison
| Feature | Semaglutide | Phentermine |
|---|---|---|
| Active ingredient | Semaglutide | Phentermine |
| Drug class | GLP-1 medication | Stimulant appetite suppressant |
| FDA-approved for | Chronic weight management | Short-term weight loss |
| Typical use | Long-term | Short-term, typically a few weeks |
| Main side-effect profile | Mostly gastrointestinal, usually transient | Can raise heart rate and blood pressure |
| Evidence | About 14.9% average loss at 68 weeks in STEP 1 | Older, short-term studies, with more modest average loss |
| At New Hope Weight Loss | Compounded, from $166 a month, not FDA-approved or brand-identical | Not offered; the clinic focuses on GLP-1 care |
How they work
- Phentermine: a stimulant that suppresses appetite; can raise heart rate and blood pressure; usually short-term; not for people with certain heart conditions.
- Semaglutide: a GLP-1 that reduces appetite and slows stomach emptying; used long-term; different side-effect profile (mostly GI).
What the evidence shows
Semaglutide has large long-term trials: in STEP 1 (PMID 33567185), about 14.9% average weight loss at 68 weeks, plus cardiovascular benefit in a specific population (SELECT, PMID 37952131). Phentermine's studies are older and short-term, with more modest average loss.
Ready to start?
$199 Skeptics' Trial, see if it works for you
One-time $199 trial with physician evaluation and, only if a prescription is approved and the dispensing pharmacy can fulfill it for the patient's location, one month of compounded semaglutide; the pharmacy confirms packaging and shipping details before fulfillment. No long-term commitment. Standard care starts with a $119 physician review; medication is separate, and compounded semaglutide programs start at $166/month.
Start the 30-day trialHow we help you choose
New Hope Weight Loss provides physician-led review of weight-management options. If a compounded prescription is considered, it is not FDA-approved or brand-identical and requires separate pharmacy verification before fulfillment. A $119 review with Dr. Sharma considers the history, including heart and blood-pressure factors, before any treatment decision.
What you can start today at New Hope Weight Loss
After a one-time $119 medical review with Dr. Sharma, eligible patients begin a physician-supervised program with compounded semaglutide from $166 a month or compounded tirzepatide from $233 a month, with a $199 one-month Skeptics' Trial. Compounded semaglutide and tirzepatide are not FDA-approved or brand-identical and have not undergone FDA premarket review for safety, effectiveness, or quality. Results vary. Any prescription depends on individualized medical review and lawful pharmacy fulfillment for the patient's location. Care is in person in Orange County and by telehealth for eligible patients in California.
Frequently asked questions
Is semaglutide better than phentermine?
They are different tools. Phentermine is an older short-term stimulant; semaglutide is a long-term GLP-1 with larger long-term trial results. The right one depends on your health history, which a physician reviews.
Can you take phentermine and semaglutide together?
That is strictly a physician decision based on your heart, blood pressure, and history. Do not combine weight-loss medications on your own.
Which causes more side effects?
They differ: phentermine is a stimulant (can affect heart rate and blood pressure); semaglutide side effects are mostly gastrointestinal and usually transient. Your physician weighs which profile fits you.
How much weight do people lose on each?
Semaglutide showed about 14.9% average loss at 68 weeks in STEP 1. Phentermine studies are older and short-term with more modest average loss. Individual results vary.
What does New Hope Weight Loss offer?
Physician-supervised compounded semaglutide and tirzepatide (not FDA-approved or brand-identical) after a $119 review, with honest guidance on what fits your situation.
This article is informational only and not medical advice. Speak with a licensed physician before starting or changing any GLP-1 therapy. Individual results vary. New Hope Weight Loss is a physician-supervised medical weight loss clinic in Costa Mesa, CA. Eligibility for treatment is determined during the medical consultation. Compounded semaglutide and compounded tirzepatide are not the same products as Wegovy®, Ozempic®, Mounjaro®, or Zepbound®.