Phentermine (generic) dosage schedule
One tablet a day, in the morning, with or without food. The FDA label sets no escalation: 37.5 mg once daily, in the morning from the first day.
Indicated as a short-term adjunct, “a few weeks” in the label's own words, and not recommended below the age of 17. There is no maintenance phase to reach and no escalation to price, which is why this drug has a schedule page and no timeline.
| When | Dose | What the label says about it |
|---|---|---|
| From day 1 | 37.5 mg once daily | There is no titration. The label sets one adult dose and says to individualize it to the lowest effective one, so the schedule for week 1 and week 12 is the same line. |
Maximum dose: 37.5 mg a day; 15 mg where eGFR is 15 to 29, and avoided entirely below 15 or on dialysis. The label sets nothing above it.
What does a month of it cost?
A pharmacy acquires the tablet for $0.068 under the federal NADAC survey — $2.05 for thirty days. Everything a subscription charges above that is dispensing margin and membership, not drug.
What happens if I miss a dose?
The label gives no missed-dose instruction. It does say late-evening administration should be avoided because of the insomnia that follows, so a dose remembered at night is the one case where the label's own words argue against catching up.
Side effects, from the same label →
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
Everything on Phentermine
- Phentermine price and terms →
- What is Phentermine? →
- Phentermine cost without insurance →
- Alternatives to Phentermine →
- Phentermine side effects →
- Does Phentermine cause constipation? →
- Does Phentermine cause diarrhea? →
- Does Phentermine make you dizzy? →
- Does Phentermine cause headaches? →
- Does Phentermine keep you awake? →
- Does Phentermine cause dry mouth? →
- How to take Phentermine →
- Which labels record what happens when you stop →
- Hair loss: which of the labels name it →
- Alcohol: what the labels say, and what they do not →
- phentermine: every product and price →
- Foundayo vs Phentermine →
- Phentermine vs Wegovy pill →
- Compounded semaglutide vs Phentermine →
- Contrave vs Phentermine →
- Compounded tirzepatide vs Phentermine →
- Ozempic vs Phentermine →
- Phentermine vs Qsymia →
- Phentermine vs Wegovy →
- Mounjaro vs Phentermine →
- Phentermine vs Saxenda →
- Phentermine vs Zepbound →
- Qsymia: the drug →
Questions
- How long does it take to reach the maintenance dose of Phentermine?
- There is no escalation to wait through: the label's dose, 37.5 mg once daily, in the morning, applies from the first day.
Every dose and interval on this page is from FDA prescribing information for phentermine hydrochloride tablets (Aurolife Pharma) , the version published 2026-06-15. Nothing here is a recommendation: the dose you take is the one your prescriber sets.