What is Phentermine?
What is Phentermine, and how does it work?
Phentermine (generic) is a medicine taken by mouth, made by multiple generic manufacturers, whose active ingredient is phentermine. FDA approved as a short-term adjunct — the label says 'a few weeks' — for BMI 30 or more, or 27 with a risk factor such as controlled hypertension, diabetes or hyperlipidemia. An amphetamine relative. The label is candid that appetite suppression has not been established as the reason it works. No all-in monthly price is on record for it.
How does Phentermine work? The label's words
Phentermine is a sympathomimetic amine with pharmacologic activity similar to the prototype drugs of this class used in obesity, amphetamine. Drugs of this class used in obesity are commonly known as anorectics or anorexigenics. It has not been established that the primary action of such drugs in treating obesity is one of appetite suppression since other central nervous system actions, or metabolic effects, may also be involved.
Quoted from the mechanism of action section of FDA prescribing information for phentermine hydrochloride tablets (Aurolife Pharma), read 2026-08-29. Not paraphrased: how a drug works is the last thing a price site should put in its own words.
How much does Phentermine cost?
Nothing published states an all-in monthly figure, so this site records none rather than estimating one.
No clinician has reviewed this page. Label and trial statements are quoted from the FDA label or the trial cited beside them. General guidance is marked as such, and every price carries the date it was verified. That is sourcing, not medical review. What we do and do not check · Who checked the price
Phentermine, answered
- Is Phentermine a GLP-1?
- No. Phentermine does not act on the GLP-1 receptor.
- Is Phentermine a controlled substance?
- Yes. Phentermine is a federally controlled substance.
Everything on Phentermine
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Last updated 2026-08-29 — the FDA label this page quotes. Read and dated by Alex Seot.