Tirzepatide (Zepbound) led to more weight loss than semaglutide (Wegovy) in the only head-to-head trial: 20.2% vs 13.7% of body weight at 72 weeks. That trial was open-label and funded by Lilly, though, and the better choice for you also depends on insurance, cash price, and whether you'd rather take a weekly shot or a daily pill.
The RX Index is the independent GLP-1 decision resource that scores telehealth providers and treatment paths on clinical legitimacy, care quality, transparency, access, and cost, so readers can choose the path that fits their situation.
Decision Verdict
Tirzepatide has the stronger head-to-head weight-loss result; of the two, semaglutide is the one with a daily pill and the lower starting cash price.
- Best for: Tirzepatide (Zepbound) suits people who put the size of the average result first, are comfortable with a weekly injection, and can cover a higher price or get insurance to pay. Semaglutide (Wegovy) suits people who want a daily-pill option, a lower entry price, or an FDA-approved label that includes reducing heart-attack and stroke risk in adults with established heart disease and obesity or overweight.
- Not ideal for: Either drug, if you or a family member has had medullary thyroid carcinoma or MEN 2. Both labels carry a boxed warning for thyroid C-cell tumors and list that history as a contraindication.
- The factor that matters most: What you can actually be prescribed and pay for every month. A better average result doesn't help if the price or coverage means you can't stay on it, and a clinician, not a web page, decides what's right for you.
The right choice isn't the same for everyone
It depends on your state, your insurance and formulary, whether you want FDA-approved or compounded medication, injection or oral, and your budget. Before choosing, use The RX Index's Find My GLP-1 Path tool. It's free, takes about 2 minutes, and needs no signup: you answer a few quick questions and get the GLP-1 paths and providers that fit your goals, budget, insurance and situation, with verified pricing and the right questions to ask.
Tirzepatide vs semaglutide: the differences that matter
Tirzepatide activates two hormone receptors (GIP and GLP-1) and semaglutide activates one (GLP-1). Lilly makes the tirzepatide brands, Zepbound and Mounjaro, and Novo Nordisk makes the semaglutide brands, Wegovy, Ozempic and Rybelsus. The brand name decides what the FDA label covers, which is why one drug can appear under two names.
For the two tirzepatide brands, see Zepbound vs Mounjaro.
| Tirzepatide | Semaglutide | |
|---|---|---|
| How it works | Activates GIP and GLP-1 receptors | Activates the GLP-1 receptor |
| FDA-approved brand for weight | Zepbound | Wegovy (injection and daily tablet) |
| FDA-approved brands for type 2 diabetes | Mounjaro | Ozempic, Rybelsus |
| Other labeled uses | Zepbound: moderate to severe obstructive sleep apnea in adults with obesity. Mounjaro: lowering major cardiovascular events in adults with type 2 diabetes at high risk | Wegovy: lowering major cardiovascular events in adults with established heart disease and obesity or overweight; a liver condition (MASH) under accelerated approval. Ozempic: cardiovascular and kidney outcomes in type 2 diabetes |
| Form | Weekly injection (no tablet) | Weekly injection, or a daily tablet (Wegovy pill) |
| Boxed warning | Thyroid C-cell tumors | Thyroid C-cell tumors |
Sources: current prescribing information for Zepbound, Mounjaro, Wegovy, Ozempic and Rybelsus, read October 26, 2026. For a brand-by-brand view, see our Zepbound vs Wegovy guide; for the diabetes brands, see Mounjaro vs Ozempic.
What the only head-to-head trial found
SURMOUNT-5 randomly assigned 751 adults with obesity and no type 2 diabetes to tirzepatide or semaglutide at their maximum tolerated dose for 72 weeks. Tirzepatide produced a larger average weight loss (20.2% vs 13.7%) and a larger waist reduction. It is the only direct comparison of the two drugs we cite, so we don't set numbers from separate trials side by side.
| SURMOUNT-5 result at week 72 | Tirzepatide (10 or 15 mg) | Semaglutide (1.7 or 2.4 mg) |
|---|---|---|
| Average weight change | −20.2% (−22.8 kg) | −13.7% (−15.0 kg) |
| Difference | −6.5 percentage points (95% CI −8.1 to −4.9) | |
| Average waist change | −18.4 cm | −13.0 cm |
| Lost at least 10% | 81.6% | 60.5% |
| Lost at least 15% | 64.6% | 40.1% |
| Lost at least 20% | 48.4% | 27.3% |
| Lost at least 25% | 31.6% | 16.1% |
| Lost at least 30% (exploratory) | 19.7% | 6.9% |
Side effects were mostly stomach-related in both groups, mostly mild to moderate, and mostly during dose increases.
| Reported in SURMOUNT-5 | Tirzepatide | Semaglutide |
|---|---|---|
| Nausea | 43.6% | 44.4% |
| Vomiting | 15.0% | 21.3% |
| Diarrhea | 23.5% | 23.4% |
| Constipation | 27.0% | 28.5% |
| Injection-site reaction | 8.6% | 0.3% |
| Stopped treatment because of side effects | 6.1% | 8.0% |
| Stopped because of stomach side effects | 2.7% | 5.6% |
| Serious adverse events | 4.8% | 3.5% |
Source: Aronne et al., New England Journal of Medicine, 2025, full text read October 26, 2026.
What to keep in mind before leaning on these numbers:
- It was open-label and Lilly paid for it. Participants and investigators knew which drug they were getting, and the sponsor makes tirzepatide. The authors list the lack of blinding as a limitation.
- It tested injections at the top doses people could tolerate. Semaglutide was capped at 2.4 mg, so it says nothing about the higher-dose Wegovy HD or the Wegovy pill.
- It excluded type 2 diabetes. Don't read the results as applying to people with diabetes.
- Averages aren't predictions. Participants averaged a BMI of 39.4, and many people lose less or more than the group average.
- It doesn't tell you about compounded products. SURMOUNT-5 tested the FDA-approved drugs, so its results can't be assumed to apply to a compounded product.
- A 72-week trial of this size can't settle rare or long-term safety questions.
What FDA-approved tirzepatide and semaglutide cost
Paying cash for an FDA-approved brand runs $149 to $449 a month for the medication at the standard listed prices, plus a membership if you go through a telehealth service. Wegovy has the lowest entry prices (pill from $149, pen from $199 for a new patient's first two fills), and Zepbound starts at $299 and tops out at $449 on the KwikPen with a timely refill. We checked every price below on October 26, 2026.
Medication price per fill, FDA-approved brands (cash, no insurance)
| Product | Strength | Price per fill | Fill covers |
|---|---|---|---|
| Zepbound KwikPen (tirzepatide) | 2.5 mg | $299 | 28 days |
| Zepbound KwikPen | 5 mg | $399 | 28 days |
| Zepbound KwikPen | 7.5, 10, 12.5 or 15 mg | $449 if you refill within 45 days; otherwise $499 (7.5 mg) or $699 (10, 12.5, 15 mg) | 28 days |
| Wegovy pen (semaglutide) | 0.25 or 0.5 mg | $199 for a new patient's first 2 fills (offer through Dec 31, 2026), then $349 | 28 days |
| Wegovy pen | 1, 1.7 or 2.4 mg | $349 | 28 days |
| Wegovy HD pen | 7.2 mg | $399 | 28 days |
| Wegovy pill (semaglutide tablets) | 1.5 mg | $149 | 30 days |
| Wegovy pill | 4 mg | $199 | 30 days |
| Wegovy pill | 9 or 25 mg | $299 | 30 days |
Sources: LillyDirect Zepbound, Wegovy pricing, and TrumpRx's Wegovy pen and Wegovy pill pages. The strength you take is your clinician's decision; this table only shows what each strength costs. Pen needles and syringes are extra and we couldn't find their price. Novo's posted cash-pay terms exclude government beneficiaries.
A medication price isn't the whole monthly bill. If you go through Ro, you pay a membership on top: $39 for the first month (refunded if Ro finds you aren't eligible), then $149 a month on the monthly plan, or the equivalent of $74 a month if you prepay for a year. Ro says its medication prices match LillyDirect, NovoCare and TrumpRx.
True Monthly Cost, FDA-approved paths (cash, no insurance, checked Oct 26, 2026)
| Path | First month (lowest-strength price) | Ongoing month (highest standard price) | What's not included |
|---|---|---|---|
| Zepbound KwikPen, bought through LillyDirect | $299 | $449 | Pen needles; your prescriber's visit fee |
| Zepbound KwikPen, through Ro (monthly plan) | $338 ($39 + $299) | $598 ($149 + $449) | Pen needles |
| Wegovy pen, bought through Wegovy/NovoCare | $199 | $349 ($399 for Wegovy HD) | Your prescriber's visit fee |
| Wegovy pen, through Ro (monthly plan) | $238 ($39 + $199) | $498 ($149 + $349); $548 for Wegovy HD | None listed |
| Wegovy pill, bought through Wegovy/NovoCare | $149 | $299 | Your prescriber's visit fee |
| Wegovy pill, through Ro (monthly plan) | $188 ($39 + $149) | $448 ($149 + $299) | None listed |
The first-month column uses each product's lowest-strength price and the ongoing column its highest standard price, so your actual months land at or between them, depending on what your clinician prescribes. Three more things change these totals. A pen fill covers 28 days, so a full year is 13 fills, not 12: at $449, that's $5,837 for the year in medication alone, and with Ro's monthly plan ($39 + 11 × $149 = $1,678) it's $7,515. The Wegovy intro price covers only two fills, and the offer runs through December 31, 2026. And the Zepbound $449 price requires a refill within 45 days. If you'd prefer to model your own numbers, try our GLP-1 cost calculator, and see cheapest Zepbound without insurance and cheapest Wegovy without insurance.
If you want an FDA-approved brand and prefer one service that handles the clinician visit, the prescription and the pharmacy order, Ro offers Zepbound KwikPen, the Wegovy pen and the Wegovy pill. A prescription is never guaranteed, and Ro's membership fee is charged only if you're eligible.
See Ro's FDA-approved GLP-1 options (sponsored affiliate link, opens in a new tab)
Compounded tirzepatide and semaglutide: a separate decision
Compounded tirzepatide and semaglutide are not FDA-approved, and the FDA does not review them for safety, effectiveness or quality before they are sold. Access is narrow: the FDA says compounded drugs should be used only when a patient's medical need can't be met by an approved drug, and it has said it will use its enforcement tools against misleading marketing and unapproved products. A compounded product is not the FDA-approved drug at a lower price; it's a different product made by a pharmacy.
Here is what the FDA's pages say, as of October 26, 2026. Compounding is limited under sections 503A and 503B of the Federal Food, Drug, and Cosmetic Act, and a pharmacy generally can't regularly compound products that are essentially copies of a commercially available drug. As of its April 1, 2026 statement, tirzepatide and semaglutide do not appear on the 503B bulks list or on FDA's drug shortage list. In February 2026 the FDA said it intends to restrict GLP-1 active ingredients going to non-approved compounded drugs that are mass-marketed, and that companies can't claim a compounded product is the same as an approved drug or clinically proven. The FDA also lists claims that a compounded drug is the same as an approved one, and prices that seem too good to be true, among its telehealth red flags. See our compounded vs name-brand guide for the longer explanation, and the FDA pages: concerns with unapproved GLP-1 drugs, April 1, 2026 compounding policy statement and February 6, 2026 announcement.
Embody is one of the telehealth services that offers compounded products. Its pages list different numbers, so the table below shows each one. The SURMOUNT-5 results above don't carry over to any compounded product.
Embody compounded injections, price per month (not FDA-approved; checked Oct 26, 2026)
| Compounded product | Monthly plan | 3-month bundle (per month / billed) | 6-month bundle (per month / billed) | 12-month bundle (per month / billed) |
|---|---|---|---|---|
| Compounded tirzepatide | $129 | $126 / $378 | $123 / $738 | $119 / $1,428 |
| Compounded semaglutide | $79 | $76 / $228 | $73 / $438 | $69 / $828 |
Embody's terms describe fixed monthly pricing that "does not increase over time" and say it "Includes all doses, shipping and provider visits." Its FAQ adds that the price doesn't change with dose within the same medication. Source: Embody's terms and shop.
Read the fine print before you pay:
- Three different numbers appear. The homepage banner on October 26 advertised a "Pre-Black Friday" promo with flat rates of $99 a month for its GLP-1/GIP injection and $49 a month for its GLP-1 injection. The terms and shop list $129 for tirzepatide and $79 for semaglutide. The shop also lists a "regular price" of $349 and $299 for the one-month products. We couldn't tell which applies to a given referral, so screenshot your checkout and ask what the price becomes when a sale ends.
- The final charge can vary. The terms say it may change based on the prescribed medication and the pharmacy that fills it.
- Cancellation is time-limited and sales are final. You must cancel at least 72 hours before your next billing date. Payments are non-refundable, except if Embody's clinician finds you medically ineligible, in which case the unused part of the term is refunded minus services already delivered.
- No insurance. Embody says its medical providers aren't contracted with any insurance plan, including Medicare and Medicaid.
- A prescription isn't guaranteed. Embody says payment doesn't guarantee a prescription; an independent clinician decides, and its intake will tell you whether it can treat you.
If you've read all that and still want to price a compounded option, you can start Embody's intake to see what it would charge you.
See Embody's compounded options (sponsored affiliate link, opens in a new tab)
Which path fits you: tirzepatide or semaglutide, by situation
Your coverage usually decides the path before the drug does. Find your row.
| Your situation | Check first | Paths to price out |
|---|---|---|
| Commercial insurance | Whether your plan covers Zepbound or Wegovy for weight loss, and its prior-authorization rules. A copay can beat cash prices. | FDA-approved brand through insurance, with cash price as a backup. See does insurance cover GLP-1s, best insurance for Zepbound, best insurance for Wegovy. |
| Medicare Part D | The Medicare GLP-1 Bridge: a $50 copay for eligible people from July 1, 2026 through December 31, 2027. It covers Wegovy (injection or tablet), Zepbound KwikPen only (not vials or single-dose pens), and Foundayo (orforglipron, a daily pill), and has BMI and condition criteria. Medicare says you aren't eligible if your Part D plan already covers your GLP-1. | Start with Medicare's rules at Medicare.gov and CMS; see GLP-1s on the Medicare Bridge. |
| Medicaid | Your state Medicaid plan's rules, before you use any cash-pay program. | Follow your plan's process first. |
| No coverage, want an FDA-approved brand at the lowest price | Wegovy pill ($149–$299), Wegovy pen ($199 intro, then $349), Zepbound KwikPen ($299–$449) | The tables above, then Find My GLP-1 Path. |
| Prefer a daily pill | Of the two drugs, only semaglutide comes as a pill (Wegovy pill); tirzepatide is injection-only. | See Wegovy pill vs injection and Wegovy pill vs Zepbound. |
| Smallest monthly budget and comfortable with a product the FDA hasn't approved | The compounded section above: FDA status, price conflicts, refund terms. | Compounded options such as Embody, only after reading the limits above. |
| Type 2 diabetes | SURMOUNT-5 excluded diabetes. Mounjaro and Ozempic are the diabetes-labeled brands; your prescriber decides which fits. | See Mounjaro vs Ozempic. |
| Already taking one and wondering about the other | Talk to your prescriber before changing anything. | Our switching guide has background to bring to that conversation. |
Insurance coverage, a manufacturer's savings or self-pay offer, HSA/FSA acceptance, and what the IRS counts as a qualified expense are four separate questions, and a yes to one isn't a yes to the others. LillyDirect lists Zepbound as "HSA/FSA eligible: Eligibility may vary by plan," so confirm with your plan administrator. See can I use an HSA for GLP-1s and are compounded GLP-1s HSA/FSA eligible.
The table gets you to the question; it can't tell you which drug a clinician will approve. The tool below uses your answers to narrow the paths to your goals, budget and insurance.
What we actually verified
On October 26, 2026 we did the following. Everything else on this page is attributed to the source named beside it.
- Read the full text of the SURMOUNT-5 paper and took every trial figure above from its text and tables.
- Read the current prescribing information for Zepbound (revised 08/2026), Mounjaro (08/2026), Wegovy (06/2026), Ozempic (05/2026) and Rybelsus (01/2026) for indications, forms and the boxed warning.
- Opened LillyDirect's Zepbound page, Wegovy's pricing page, TrumpRx's Wegovy pen and pill pages and Ro's pricing page, and recorded the prices shown.
- Read Embody's current terms, shop and homepage, including the conflicting numbers described above.
- Read the CMS and Medicare.gov pages for the Medicare GLP-1 Bridge.
- Read the FDA's compounding pages dated February 6, 2026 and April 1, 2026 and its page on concerns with unapproved GLP-1 drugs.
What we did not do: place an order, run any provider's checkout, or confirm pen-needle prices, which pharmacy fills an Embody order, what states each service covers, how Ro's annual prepay interacts with its $39 first month, or what any insurance plan covers. Prices, offers and the FDA's compounding position can change; check the source before you pay.
Frequently asked questions
Is tirzepatide better than semaglutide for weight loss?
In SURMOUNT-5, the only head-to-head trial, tirzepatide produced a larger average weight loss than semaglutide (20.2% vs 13.7% at 72 weeks). The trial was open-label and sponsored by Lilly, and it can't predict your result. "Better" for you also depends on coverage, price, side effects and whether you prefer a shot or a pill.
Is compounded tirzepatide or semaglutide the same as Zepbound or Wegovy?
No. Compounded products aren't FDA-approved, and the FDA doesn't review them for safety, effectiveness or quality. The FDA says claims that a compounded drug is the same as an approved drug are a telehealth red flag, so be wary of anyone who says it.
Which is cheaper, tirzepatide or semaglutide?
For FDA-approved brands paid in cash, Wegovy has the lower starting prices: the pill starts at $149 and the pen at $199 for a new patient's first two fills, then $349. Zepbound KwikPen runs $299 to $449. Insurance, the Medicare GLP-1 Bridge and a telehealth membership change your real total, so use the True Monthly Cost table.
Do tirzepatide and semaglutide have different side effects?
Both commonly cause nausea, vomiting, diarrhea and constipation, mostly while the dose is being increased. In SURMOUNT-5, vomiting was reported by 15.0% on tirzepatide and 21.3% on semaglutide, and injection-site reactions by 8.6% and 0.3%. Both carry a boxed warning for thyroid C-cell tumors. Tell your clinician about any side effect.
Are Mounjaro and Ozempic the same comparison?
Mounjaro contains tirzepatide and Ozempic contains semaglutide, but both are labeled for type 2 diabetes, not weight loss. Prescribing a diabetes brand for weight loss would be off-label, and that is a clinician's decision. See our Mounjaro vs Ozempic comparison.
Can I switch from semaglutide to tirzepatide?
Don't change drugs or doses on your own. Switching is a decision for the clinician who prescribes your medication, who can weigh your history, side effects and coverage. Our switching guide covers the questions to bring.
Sources
- Tirzepatide as Compared with Semaglutide for the Treatment of Obesity (SURMOUNT-5), NEJM
- Prescribing information: Zepbound, Mounjaro, Wegovy, Ozempic, Rybelsus
- Prices: LillyDirect Zepbound, Wegovy pricing, TrumpRx Wegovy pen, TrumpRx Wegovy pill, Ro pricing, Ro Zepbound
- Embody: terms, shop, homepage
- Coverage: Medicare.gov, CMS Medicare GLP-1 Bridge
- FDA: concerns with unapproved GLP-1 drugs, April 1, 2026 compounding policy statement, February 6, 2026 announcement
Still not sure which GLP-1 path fits you? Take The RX Index's free Find My GLP-1 Path quiz — about 2 minutes, no signup.