Mounjaro (tirzepatide, diabetes label) vs Phentermine (generic)
Neither comes out ahead on the axes compared here. Mounjaro scores higher on the published halfrx formula, 5.1 against 3.1; the formula takes in more than this table does.
Computed from the stored fields, so it moves when a price does. Nothing here is written by hand or by a model.
Mounjaro (tirzepatide, diabetes label) or Phentermine (generic): which one has a price?
Only Mounjaro (tirzepatide, diabetes label) has an all-in figure here: $499 a month, read from its own page on 2026-09-21. No price is published here for Phentermine (generic), so price cannot decide between them. Every axis below is computed from stored fields rather than written by hand, so the comparison moves when a price does. Neither carries an FTC action, a state action, a BBB F grade or an FDA warning letter. One is branded and the other generic, and they are different drugs, so the gap is the molecule as well as the price. The published formula scores them 5.1 and 3.1 out of 10, arithmetic over the same stored fields rather than an editor's preference. Cost here is scored on what a patient pays once titrated, never on the entry price, because an introductory rate covers the months before anybody has reached the dose they stay on.
Head to head
| What decides it | Mounjaro $499/mo | Phentermine price unverified |
|---|---|---|
| Entry priceNot comparable — Phentermine (generic) publishes no verified all-in price. | not comparable | not comparable |
| Regulatory and complaint riskNeither carries a lawsuit, an FDA warning letter or a supply-risk flag. | tied | tied |
What the trials, the titration and a year actually say
| Axis | Mounjaro | Phentermine |
|---|---|---|
| The trial that figure comes from | No percentage of body weight appears anywhere on the Mounjaro label, which has no weight-management section: every trial on it is a diabetes trial and reports weight in kilograms. This figure is worked out from the label's own kilograms — 11.2 kg lost from a 93.8 kg mean baseline at week 40 on 15 mg, in SURPASS-2 against semaglutide — and is an arithmetic step the label does not take. | The label does not carry a modern trial figure; it states in its own words that the usefulness of this class 'should be measured against possible risk factors', and it is not recommended for long-term use. |
| Maintenance dose | 2.5 mg to 15 mg once weekly, set by blood sugar control | 37.5 mg once daily, in the morning |
| Year one at the published price of every step | $6,487 | No titration prices recorded |
The year-one figures are one price at every dose, times the thirteen fills a 28-day month bills. The full arithmetic is published.
What separates these two, price aside
- These are different molecules — tirzepatide against phentermine — so this is a comparison of two treatments, not of two prices for one.
Mounjaro (tirzepatide, diabetes label)
Pros
Cons
- −Off-label for weight loss without diabetes — expect insurance denial and prescriber reluctance.[4]
- −Self-pay is $499 a month at every strength through LillyDirect, with no cheaper starting tier: Zepbound, the same molecule on the weight-loss label, is $299 at 2.5 mg and $449 at 7.5 mg and above through the same pharmacy. For weight loss, Zepbound is the cheaper route to the same molecule.[1]
- −Weekly injection with the same GI side-effect profile.[4]
Sources
- [1] Mounjaro self-pay price, LillyDirect ($499 a month at every strength)
- [2] Mounjaro Savings Card terms, Lilly ($499 a month with commercial insurance that does not cover it)
- [3] GLP-1 weight loss cost 2026
- [4] FDA prescribing information for MOUNJARO
- [5] TrumpRx, the federal direct-purchase price site — $499 a month, single-dose pen, read 6 September 2026
Phentermine (generic)
Pros
- +Pharmacies acquire it at $0.068 a tablet, about $2 for a 30-day supply, under the federal NADAC survey. That is what a pharmacy pays, not what it charges you.[2]
- +Covered by more Medicaid programs than any GLP-1 — seven states cover an older weight-loss agent while covering no GLP-1 at all.[3]
- +One tablet each morning, no injection, no titration schedule beyond a possible half dose.[1]
Cons
- −Approved for a few weeks only. Every monthly subscription selling it as ongoing therapy is using it off the label's own duration.[1]
- −Schedule IV controlled substance, chemically related to the amphetamines, with the dependence warnings that follow from that.[1]
- −Stopping after prolonged high dosing brings extreme fatigue and depression, per the label — which is a hard exit from a subscription that sold it as maintenance.[1]
- −No cardiovascular outcome data of the kind the GLP-1s now carry, and contraindicated where blood pressure is uncontrolled.[1]
Comparisons are computed from the fields on each card, not written by hand or by a model, so they change when the data does. Information only, not medical advice. halfrx may earn a commission from some links, which never changes what a comparison says.
Everything on Mounjaro
- Mounjaro price and terms →
- What is Mounjaro? →
- Mounjaro cost without insurance →
- Alternatives to Mounjaro →
- Mounjaro coupons and savings cards →
- Mounjaro Savings Card →
- Mounjaro side effects →
- Does Mounjaro make you feel sick? →
- Does Mounjaro cause constipation? →
- Does Mounjaro cause diarrhea? →
- Does Mounjaro make you throw up? →
- Does Mounjaro cause stomach pain? →
- Does Mounjaro cause indigestion? →
- Does Mounjaro take away your appetite? →
- Mounjaro dose schedule →
- How to inject Mounjaro →
- How long Mounjaro takes to work →
- 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 →
- tirzepatide at LillyDirect: the price →
- tirzepatide: every product and price →
- LillyDirect: the seller →
- Mochi Health: the seller →
- Henry Meds: the seller →
- Noom Med: the seller →
- PlushCare: the seller →
- Compounded tirzepatide: the drug →
- Eden: the seller →
- GoodRx for Weight Loss: the seller →
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? →
- Phentermine dose schedule →
- 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 →
- Qsymia: the drug →
Mounjaro against Phentermine, answered
- Is Mounjaro or Phentermine better for weight loss?
- Only Mounjaro has a trial figure recorded here: 11.9% average weight loss, worked out from the kilograms on its label. Phentermine has none on this site, so the two cannot be compared on effect and this page does not pick one on it.
- Which is cheaper, Mounjaro or Phentermine?
- Phentermine publishes no all-in monthly price that could be verified, so this page carries no comparison rather than an estimate — and an unpublished price is itself worth weighing.
- Can you switch between Mounjaro and Phentermine?
- They are different molecules, so this is a change of medication rather than of brand, and the one you move to is started on its own dosing schedule.