Searching for the most effective weight loss medication? You’ve likely come across Semaglutide and Phentermine—two very different approaches to medical weight management. But which one is right for you?
At Skin Works Medical Spa, we offer both options depending on your health profile and goals. In this article, we compare their mechanisms, results, safety, and ideal use cases so you can make an informed choice with guidance from medical professionals.
What Are Semaglutide and Phentermine?
🔬 Semaglutide:
- GLP-1 receptor agonist developed for type 2 diabetes
- Controls blood sugar, reduces appetite, and slows digestion
- FDA-approved for chronic weight management (Wegovy)
- Injected once weekly
📖 Learn more on our Semaglutide weight loss page
🔬 Phentermine:
- Appetite suppressant in the amphetamine family
- Stimulates the central nervous system to reduce hunger
- FDA-approved since 1959 for short-term weight loss
- Taken orally, typically once daily
📖 Read about our Tirzepatide Medical Weight Loss Program
How Do They Work Differently?
| Feature | Semaglutide | Phentermine |
|---|---|---|
| Mechanism | GLP-1 receptor agonist | CNS stimulant & appetite suppressant |
| Method | Weekly injection | Daily oral tablet |
| FDA Approval | Chronic weight management (2021) | Short-term weight loss (1959) |
| Weight Loss Results | Up to 15% body weight (STEP trials) | 5%–10% on average |
| Duration | Long-term | Short-term (≤12 weeks) |
| Addictive Risk | None | Low to moderate |
*Based on STEP, Obesity, and Look AHEAD studies*
Who Is Each Medication Best For?
✅ Semaglutide May Be Ideal If You:
- Have a BMI ≥30 or ≥27 with weight-related conditions
- Want long-term weight reduction with metabolic support
- Prefer a once-a-week solution
- Have diabetes or prediabetes
✅ Phentermine May Be Ideal If You:
- Need a short-term weight loss boost
- Want a low-cost daily option
- Don’t have cardiac or stimulant-related risk factors
- Are not a candidate for injectables
Side Effects & Safety
Semaglutide: Common side effects include nausea, constipation, and fatigue. These are dose-dependent and typically decrease over time.
Phentermine: May cause insomnia, increased heart rate, restlessness, and dry mouth. Not suitable for patients with heart issues, high blood pressure, or anxiety disorders.
Both medications should be prescribed under medical supervision. At Skin Works, we conduct full evaluations to ensure safe and effective treatment.
Which One Works Faster?
Phentermine acts fast—appetite suppression kicks in within hours. However, **weight loss plateaus quickly** and usually rebounds if not paired with long-term lifestyle changes.
Semaglutide shows slower but more sustainable results—studies show consistent reduction over several months, with long-term maintenance possible through ongoing treatment and support.
How We Support Your Weight Loss Journey
Whether you choose Semaglutide, Phentermine, or a combination approach, our programs include:
- Full medical evaluation & lab testing
- Board-certified provider supervision
- Custom dosage planning
- Ongoing progress check-ins
- Nutrition & activity coaching
Final Thoughts: Semaglutide vs. Phentermine
There’s no one-size-fits-all answer. Your body, health status, and weight loss goals all play a role. That’s why our licensed providers offer personalized evaluations to help you decide the best course of action—short-term, long-term, or both.
🎯 Take the first step today with a free consultation at Skin Works Medical Spa.
References
- FDA Label for Wegovy (Semaglutide)
- FDA Label for Adipex-P (Phentermine)
- STEP Clinical Trial – NEJM
- Phentermine Efficacy & Safety Review
Disclaimer: This article is for educational purposes only. Always consult a licensed healthcare provider before starting any medication or program.