Phentermine vs Semaglutide for Weight Loss: What to Know

What Is Semaglutide?

Semaglutide is a GLP-1 receptor agonist, a class of medications that mimic the body’s natural GLP-1 hormone to support blood sugar regulation, appetite control, and digestive function.

FDA-approved semaglutide products include:

• Wegovy® – indicated for chronic weight management in certain adults with overweight or obesity
  
• Ozempic® – approved for type 2 diabetes management
  
• Rybelsus® – an oral GLP-1 option also approved for type 2 diabetes
  
  

Eden does not dispense compounded semaglutide. We connect patients with licensed healthcare providers who may prescribe FDA-approved GLP-1 therapies if clinically appropriate.

‍

How Semaglutide Supports Weight Management

Semaglutide works by:

• Reducing appetite by acting on satiety centers in the brain
  
• Slowing gastric emptying, helping you feel full longer
  
• Regulating insulin and glucagon to support balanced glucose metabolism
  
• Reducing cravings for calorie-dense or highly processed foods
  
  

These effects contribute to metabolic improvements and weight-related outcomes when paired with behavioral and dietary support.

‍

What Is Phentermine?

Phentermine is a sympathomimetic stimulant approved by the FDA for short-term weight loss treatment (typically 12 weeks or less). It is often prescribed to adults with a BMI of 30 or higher, or 27 or higher with weight-related conditions.

Common phentermine formulations include:

• Adipex-P®
  
• Lomaira®
  
• Suprenza®
  
• Qsymia® (phentermine combined with topiramate)
  
  

Due to its similarity to amphetamines, phentermine is a controlled substance and must be used cautiously under close medical supervision.

‍

How Phentermine Works

Phentermine supports short-term weight reduction by:

• Stimulating the central nervous system to suppress appetite
  
• Increasing norepinephrine and related neurotransmitters to reduce hunger
  
• Temporarily altering hunger cues and energy regulation
  
  

Its effects often peak within a few weeks, and discontinuation may lead to rebound appetite or weight regain.

‍

Phentermine vs Semaglutide: Weight Loss Results

Semaglutide

Clinical trials, including the STEP program, have shown that patients using semaglutide as part of a structured treatment plan may lose an average of 15 percent or more of their body weight over 6 to 12 months. These outcomes are best maintained with long-term medical oversight, physical activity, and nutrition support.

Phentermine

Studies show phentermine may lead to 5 to 10 percent weight loss over 8 to 12 weeks. However, most patients regain some or all of the lost weight after discontinuation, particularly without continued lifestyle changes.

Individual results vary. Sustainable weight management depends on factors like adherence, behavior, nutrition, and medical history.

‍

Side Effects and Safety Profiles

Semaglutide

Semaglutide is known to sometimes lead to the following potential side-effects in some people:

• Common: Nausea, vomiting, diarrhea, constipation, abdominal discomfort
  
• Rare but serious: Thyroid C-cell tumors (avoid in patients with a personal or family history of medullary thyroid carcinoma or multiple endocrine neoplasia syndrome type 2)
  
• Monitoring: Gradual dose escalation is used to minimize gastrointestinal effects
  
  

Phentermine

Phentermine can lead to the following potential side-effects in some people:

• Common: Dry mouth, insomnia, jitteriness, dizziness
  
• Risks: Elevated heart rate, increased blood pressure, mood changes, dependence
  
• Contraindications: History of heart disease, hyperthyroidism, glaucoma, uncontrolled hypertension
  
  

Always review your full health history with a licensed provider before beginning any weight loss medication.

‍

Cost Comparison: Phentermine vs Semaglutide

• Phentermine: Generally low cost (as little as $14 per month), widely covered or affordable out of pocket
  
• Semaglutide: Higher monthly cost ($900 to $1,300) if not covered by insurance. Some patients pay out of pocket when not approved for weight loss use
  
  

Eden’s care team helps patients understand coverage options and connects them with providers who can create cost-conscious treatment plans.

‍

Pros and Cons at a Glance

Semaglutide Pros

• Long-term weight support
  
• Supports blood sugar balance
  
• Lower risk of dependency
  
• Weekly or oral dosing options
  
  

Semaglutide Cons

• Higher cost
  
• Injectable in most formulations
  
• Gastrointestinal side effects are common during ramp-up
  
  

Phentermine Pros

• Low cost
  
• Fast-acting appetite suppressant
  
• Short-term use may help kickstart weight loss
  
  

Phentermine Cons

• Not suitable for long-term use
  
• High risk of cardiovascular and stimulant-related side effects
  
• Regain of weight is common post-treatment
  ‍

‍

Final Thoughts: Which Is Right for You?

When comparing phentermine vs semaglutide, the right choice depends on your health goals, tolerance, and risk factors. Phentermine may be appropriate for short-term appetite suppression, while semaglutide offers a longer-term strategy for metabolic support and sustained weight-related improvements.

At Eden, we connect patients with licensed medical providers who tailor weight care plans based on your health profile. Whether you're just starting your journey or looking for long-term metabolic support, our network offers expert guidance every step of the way.

‍

Disclaimer

This article is for informational purposes only and should not be interpreted as medical advice. Eden does not prescribe medications or manufacture any pharmaceutical products. All prescriptions, treatment decisions, and health evaluations are conducted by licensed third-party providers in accordance with applicable laws.

‍