Phentermine is an appetite suppressant that has been used for weight loss for decades. It is typically taken as a short-term adjunct (weeks to a few months) and works by stimulating the central nervous system to reduce appetite. GLP-1 medications like semaglutide and tirzepatide are newer, taken long-term, and work through appetite, fullness, and blood-sugar pathways.
How the profiles differ
Phentermine is inexpensive, widely prescribed, and effective in the short term, but it is a controlled substance with stimulant-like side effects (insomnia, elevated heart rate, jitteriness) and is generally not intended for long-term use. GLP-1s have stronger long-term trial data but a higher monthly cost and more gastrointestinal side effects. Some providers combine approaches; others prefer one based on your history, blood pressure, and tolerance for stimulants.
| Factor | Phentermine | GLP-1 medications |
|---|---|---|
| Typical use | Short-term (weeks–months) | Long-term |
| Average loss | Modest, often regained | ~15–22% in trials |
| Cost | Low (often <$100/month) | ~$1,300/month list |
| Common side effects | Insomnia, elevated heart rate, jitteriness | Nausea, GI upset |
| Controlled substance | Yes (Schedule IV) | No |
- You want a low-cost option to try first.
- You have no history of high blood pressure or heart conditions (phentermine raises heart rate).
- You need a short-term assist while you build habits.
Choose Phentermine if…
<Choose GLP-1 if…
uNot sure where to start?
That is exactly what a consultation is for. Tell a qualified provider what you are experiencing and what matters most to you — price, side effects, convenience, or results — and let them help you weigh the options. You can also use the matching quiz to be connected with Boca Raton providers who offer the type of care you are interested in.
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