Compounded Semaglutide vs Tirzepatide: Dosage Charts, Cost, Side Effects & 2026 Legal Status

Key takeaways

Semaglutide activates one receptor (GLP-1); tirzepatide activates two (GIP and GLP-1). In the only head-to-head trial in adults with obesity and no diabetes, tirzepatide produced 20.2% weight loss at 72 weeks versus 13.7% for semaglutide, each at its maximum tolerated dose.
Every efficacy and safety number on this page comes from the brand products. No compounded version has ever been tested in a trial; the best a compounded vial can do is match the brand.
The label titration schedules are the only dosing with evidence behind them. Compounded vials convert those milligram doses into insulin-syringe units, and FDA has logged overdoses of 5 to 20 times the intended dose from that conversion.
Weight comes back when the drug stops: two-thirds of the loss returned within a year in the semaglutide extension study, and people switched from tirzepatide to placebo regained 14% in a year. Microdosing has no trial behind it at all.
Since the shortages ended (tirzepatide December 2024, semaglutide February 2025), compounded copies are legal only for a documented individual need. In 2026 FDA sent 55 warning letters to telehealth companies, proposed removing both drugs from the 503B list, and said adding vitamin B12 does not make a copy legal.

How semaglutide and tirzepatide work

Both drugs are synthetic peptides that copy hormones your gut releases after a meal. GLP-1 (glucagon-like peptide-1) is made in the lower small intestine; it tells the pancreas to release insulin when glucose is high, suppresses glucagon, slows the stomach, and signals the brain that you have eaten. The natural hormone is destroyed within minutes. Semaglutide is human GLP-1 with two amino acids swapped to block that destruction and a fatty-acid chain that makes it cling to albumin in the blood. The result lasts about a week, which is why it is injected weekly and why it is still in the body five to seven weeks after the last dose (Wegovy label).

Tirzepatide is a single peptide engineered to activate two receptors at once: the GLP-1 receptor and the GIP receptor. GIP (glucose-dependent insulinotropic polypeptide) comes from the upper small intestine and also boosts insulin after meals, but it acts on fat tissue and on brain circuits differently from GLP-1. Why adding GIP produces more weight loss is still debated; the leading explanations are an additional appetite signal in the brain and a tolerability advantage that lets people stay on a stronger total incretin effect. What is not debated is the result, which the head-to-head trial below made explicit.

"Compounded" changes none of this chemistry. A compounding pharmacy buys semaglutide or tirzepatide as a bulk powder, dissolves it, and fills it into multi-dose vials that you draw up with an insulin syringe. The active ingredient is meant to be the same molecule; what differs is who verified it, how it is dosed, and whether the pharmacy may legally make it at all. The legal tracker covers the rules; this page covers the drugs.

Head to head: what the trials show

SURMOUNT-5: the only direct comparison in obesity

Until 2025 the two drugs had only been compared across different trials. SURMOUNT-5 put them in the same one: 751 adults with obesity but not diabetes were randomized to the maximum tolerated dose of tirzepatide (10 or 15 mg weekly) or of semaglutide (1.7 or 2.4 mg weekly) for 72 weeks. Mean weight loss was 20.2% with tirzepatide and 13.7% with semaglutide; waist circumference fell 18.4 cm versus 13.0 cm; and more tirzepatide participants reached every threshold from 10% to 25% loss. The most common side effects in both groups were gastrointestinal, mostly mild to moderate, and clustered in the escalation phase (Aronne 2025). The trial was open-label, meaning participants knew which drug they had, and it was funded by tirzepatide's manufacturer; neither fact explains a 6.5-point gap in measured body weight.

STEP 1 and SURMOUNT-1: the pivotal trials

STEP 1 randomized 1,961 adults with obesity (or overweight plus one weight-related condition), without diabetes, to semaglutide 2.4 mg or placebo for 68 weeks. Mean weight loss was 14.9% versus 2.4%; 86% of the semaglutide group lost at least 5% of their weight and half lost at least 15%. Nausea and diarrhea were the most common adverse events, and 4.5% stopped because of gastrointestinal effects versus 0.8% on placebo (Wilding 2021).

SURMOUNT-1 randomized 2,539 similar adults to tirzepatide 5, 10 or 15 mg or placebo for 72 weeks. Mean weight loss was 15.0%, 19.5% and 20.9% versus 3.1%; 57% of the 15 mg group lost at least a fifth of their body weight versus 3% on placebo. Adverse events led to discontinuation in 4.3%, 7.1% and 6.2% of the tirzepatide groups versus 2.6% on placebo (Jastreboff 2022).

SURPASS-2: type 2 diabetes

In 1,879 people with type 2 diabetes, 40 weeks of tirzepatide 5, 10 or 15 mg lowered HbA1c by 2.01, 2.24 and 2.30 percentage points, versus 1.86 with semaglutide 1 mg (the diabetes dose, not the 2.4 mg obesity dose), and produced 1.9, 3.6 and 5.5 kg more weight loss. Nausea (17 to 22% versus 18%), diarrhea and vomiting were similar between the drugs (Frías 2021).

SELECT: the heart

Semaglutide has one result tirzepatide cannot yet match on its obesity label. In SELECT, 17,604 adults with existing cardiovascular disease and a BMI of 27 or more, without diabetes, took semaglutide 2.4 mg or placebo for a mean of 40 months. Cardiovascular death, heart attack or stroke occurred in 6.5% on semaglutide versus 8.0% on placebo, a 20% relative reduction (Lincoff 2023). That trial is why the Wegovy label carries a cardiovascular risk-reduction indication, alongside weight reduction and a liver indication (non-cirrhotic MASH with moderate to advanced fibrosis). Zepbound's label lists weight reduction and moderate to severe obstructive sleep apnea in adults with obesity (Zepbound label).

Semaglutide and tirzepatide claims, graded by the evidence behind them
Claim	Grade	What the evidence shows	Sources
Semaglutide 2.4 mg produces about 15% weight loss	A	STEP 1: 1,961 adults with obesity, 68 weeks, mean loss 14.9% versus 2.4% with placebo; half of the semaglutide group lost at least 15%.	Wilding 2021
Tirzepatide produces 15 to 21% weight loss depending on dose	A	SURMOUNT-1: 2,539 adults, 72 weeks, mean loss 15.0% (5 mg), 19.5% (10 mg) and 20.9% (15 mg) versus 3.1% with placebo.	Jastreboff 2022
Tirzepatide beats semaglutide head to head in obesity without diabetes	A	SURMOUNT-5: 751 adults, 72 weeks, open-label; 20.2% versus 13.7% at maximum tolerated doses; waist circumference down 18.4 cm versus 13.0 cm.	Aronne 2025
Tirzepatide lowers HbA1c and weight more than semaglutide 1 mg in type 2 diabetes	A	SURPASS-2: 1,879 patients, 40 weeks; HbA1c down 2.01 to 2.30 points versus 1.86; 1.9 to 5.5 kg more weight loss; similar gastrointestinal rates.	Frías 2021
Semaglutide reduces heart attacks, strokes and cardiovascular death in people with heart disease and obesity	A	SELECT: 17,604 adults, mean follow-up 40 months; primary event in 6.5% versus 8.0% (hazard ratio 0.80). No equivalent obesity-population outcomes trial has reported for tirzepatide.	Lincoff 2023
Weight returns after stopping	A	STEP 1 extension: two-thirds of lost weight regained within a year off semaglutide (net loss 5.6% at week 120). SURMOUNT-4: switching to placebo after 36 weeks of tirzepatide produced a 14% regain over 52 weeks versus a further 5.5% loss with continued treatment.	Wilding 2022; Aronne 2024
Gastrointestinal side effects are the main cost of treatment	A	Wegovy label: nausea 44% versus 16%, vomiting 24% versus 6%; 6.8% versus 3.2% discontinued for adverse reactions. Zepbound label: nausea 25 to 29% versus 8%; 4.8 to 6.7% versus 3.4% discontinued.	Wegovy label; Zepbound label
Part of the weight lost is lean mass	B	Across GLP-1 trials with body-composition substudies, lean mass accounted for roughly 15% to as much as 40 to 60% of total weight lost; MRI studies suggest muscle changes are largely proportionate to the weight loss, with risk concentrated in older adults.	Neeland 2024
Microdosing gives the benefits with fewer side effects	D	No randomized trial of sub-label doses or stretched intervals exists as of October 2026; the published literature is commentary describing evidence gaps. The lowest label doses are starting doses, and the Zepbound label states 2.5 mg is not approved for maintenance.	Komé 2025; Zepbound label
Compounded versions perform the same as the brand	D	Never tested. FDA has documented dosing errors of 5 to 20 times the intended dose with compounded vials, products made from salt forms of semaglutide that are not the approved active ingredient, and adverse event reports it cannot evaluate.	FDA dosing-error alert 2024; FDA GLP-1 concerns page

A = strong human trials or meta-analyses · B = small or short human trials · C = observational, mechanistic or indirect human data · D = animal/in-vitro only, or no evidence. Grades describe the evidence, not whether we recommend the use.

Three things to hold onto from that table. First, the gap between the drugs is real but smaller than the gap between either drug and nothing: semaglutide's 15% is still more than any older weight-loss medication achieved. Second, the only outcomes beyond the scale, fewer heart attacks and strokes, belong to semaglutide so far. Third, not one of these trials used a compounded product. When a telehealth site quotes "up to 20% weight loss" for its compounded tirzepatide, it is quoting Lilly's trial of Lilly's product.

Side effects: the numbers from the labels

The labels report adverse reactions from the pooled placebo-controlled weight-reduction trials: three trials of up to 68 weeks for Wegovy 2.4 mg (2,116 patients versus 1,261 on placebo) and two trials of up to 72 weeks for Zepbound (630, 948 and 941 patients at 5, 10 and 15 mg versus 958 on placebo) (Wegovy label) (Zepbound label).

Adverse reaction (% of patients)	Wegovy 2.4 mg vs placebo	Zepbound 5 / 10 / 15 mg vs placebo
Nausea	44 vs 16	25 / 29 / 28 vs 8
Diarrhea	30 vs 16	19 / 21 / 23 vs 8
Vomiting	24 vs 6	8 / 11 / 13 vs 2
Constipation	24 vs 11	17 / 14 / 11 vs 5
Abdominal pain	20 vs 10	9 / 9 / 10 vs 5
Dyspepsia (indigestion)	9 vs 3	9 / 9 / 10 vs 4
Fatigue	11 vs 5	5 / 6 / 7 vs 3
Headache	14 vs 10	not listed (under 2% above placebo)
Injection-site reactions	not listed	6 / 8 / 8 vs 2
Eructation (burping)	7 vs under 1	4 / 5 / 5 vs 1
Reflux (GERD)	5 vs 3	4 / 4 / 5 vs 2
Dizziness	8 vs 4	4 / 5 / 4 vs 2
Hair loss	3 vs 1	5 / 4 / 5 vs 1
Stopped treatment because of adverse reactions	6.8 vs 3.2	4.8 / 6.3 / 6.7 vs 3.4
Stopped because of gastrointestinal reactions	4.3 vs 0.7	1.9 / 3.3 / 4.3 vs 0.5
Gallstones (cholelithiasis)	1.6 vs 0.7	1.1 vs 1.0 (cholecystitis 0.7 vs 0.2)
Acute pancreatitis (adjudicated)	0.2 vs under 0.1 cases per 100 patient-years	0.14 vs 0.15 cases per 100 patient-years
Acute kidney injury	0.4 vs 0.2 cases per 100 patient-years	0.5 vs 0.2% of patients
Resting heart rate	mean increase 1 to 4 beats per minute	mean increase 1 to 3 beats per minute

Two cautions when reading the table side by side. These are different trials in different populations (a quarter of the Zepbound pool had type 2 diabetes versus a fifth of the Wegovy pool), so the rows are not a head-to-head comparison; in the trials that did compare the drugs directly, SURMOUNT-5 and SURPASS-2, gastrointestinal profiles were similar. And "nausea 44%" means any nausea reported at any time over 68 weeks; the labels say most nausea, vomiting and diarrhea occurs during dose escalation and fades.

Some rows deserve a sentence each. Gallbladder disease is more common on both drugs, partly because rapid weight loss itself causes gallstones; the Wegovy label notes the excess persisted even after accounting for the amount of weight lost. Acute pancreatitis is rare on both and the labels tell clinicians to stop the drug if it is suspected. Hair loss tracks the weight loss and affected women far more than men (7.1% versus 0.5% on Zepbound). Dysesthesia, abnormal skin sensations such as burning or tingling, appears at 2% with Wegovy 2.4 mg, but at 22% with the 7.2 mg dose (Wegovy HD) now on the label, a reminder that higher doses are not free. Finally, the earlier warning about suicidal thoughts was removed from the Wegovy label in February 2026 and no longer appears on the Zepbound label; serious hypersensitivity reactions, ileus and pulmonary aspiration during anesthesia remain on both.

Dosage charts

Wegovy (semaglutide) label schedule

Weeks	Once-weekly subcutaneous dose
1 to 4	0.25 mg (starting dose)
5 to 8	0.5 mg
9 to 12	1 mg
13 to 16	1.7 mg
17 onward	2.4 mg maintenance (1.7 mg is an approved alternative for weight reduction and cardiovascular risk reduction)
Optional	7.2 mg (Wegovy HD) for patients who tolerate 2.4 mg for at least 4 weeks and need more weight reduction

If a dose is not tolerated, the label says to delay the next step by four weeks; if two or more consecutive doses are missed, escalation restarts at a lower dose. The Wegovy tablet, approved for adults, starts at 1.5 mg daily for 30 days and escalates every 30 days to a 25 mg maintenance dose (Wegovy label).

Zepbound (tirzepatide) label schedule

Weeks	Once-weekly subcutaneous dose
1 to 4	2.5 mg (initiation only; not approved as a maintenance dose)
5 to 8	5 mg
Then	increase by 2.5 mg no sooner than every 4 weeks: 7.5 mg, 10 mg, 12.5 mg, 15 mg
Maintenance	5, 10 or 15 mg for weight reduction (10 or 15 mg for sleep apnea); 15 mg is the maximum

The label tells prescribers to weigh response and tolerability in choosing the maintenance dose and to consider a lower maintenance dose if a higher one is not tolerated (Zepbound label). Both drugs are injected into the abdomen, thigh or upper arm; see how to inject peptides for technique.

Compounded vials: converting milligrams to units

Brand pens deliver a fixed milligram dose. Compounded products are usually dispensed as a solution in a multi-dose vial at a labeled concentration, and the dose is drawn up with a U-100 insulin syringe, on which 100 units equal 1 mL. The conversion is:

units = dose in mg ÷ concentration in mg/mL × 100

The tables below use example concentrations to show the arithmetic. Pharmacies dispense many different concentrations, so your vial may differ; the only number that matters is the one on your label, and the units converter and peptide calculator will run it for any concentration.

Semaglutide label dose	Vial at 2.5 mg/mL	Vial at 5 mg/mL
0.25 mg	0.1 mL = 10 units	0.05 mL = 5 units
0.5 mg	0.2 mL = 20 units	0.1 mL = 10 units
1 mg	0.4 mL = 40 units	0.2 mL = 20 units
1.7 mg	0.68 mL = 68 units	0.34 mL = 34 units
2.4 mg	0.96 mL = 96 units	0.48 mL = 48 units

Tirzepatide label dose	Vial at 10 mg/mL	Vial at 20 mg/mL
2.5 mg	0.25 mL = 25 units	0.125 mL = 12.5 units (half-unit syringe)
5 mg	0.5 mL = 50 units	0.25 mL = 25 units
7.5 mg	0.75 mL = 75 units	0.375 mL = 37.5 units
10 mg	1 mL = 100 units (a full 1 mL syringe)	0.5 mL = 50 units
12.5 mg	1.25 mL, more than one syringe	0.625 mL = 62.5 units
15 mg	1.5 mL, more than one syringe	0.75 mL = 75 units

This arithmetic is where compounded GLP-1s hurt people. In July 2024 FDA issued an alert after receiving reports of patients who had injected 5 to 20 times the intended dose of compounded semaglutide, mostly by drawing the wrong volume from a vial: one patient told to draw 5 units (0.05 mL) drew 50 units instead. Other reports involved prescribers converting milligrams to units incorrectly, producing five- to ten-fold overdoses. Patients reported severe nausea and vomiting, hypoglycemia, fainting, dehydration and pancreatitis, and some were hospitalized (FDA dosing-error alert). A prescription that states the dose in milligrams, the concentration in mg/mL and the resulting units, with the syringe size specified, prevents nearly all of it.

Microdosing: what the claims rest on

"Microdosing" means taking less than the label starting dose (for example 0.1 mg of semaglutide or 1 mg of tirzepatide a week), or stretching the interval to 10 or 14 days, on the promise of appetite control with fewer side effects, cheaper maintenance, or vague metabolic and anti-inflammatory benefits. It is a large search term and a growing telehealth product.

Here is the evidence base. As of October 2026 PubMed indexes no randomized trial of sub-label dosing or stretched intervals of either drug; what exists is commentary, such as a 2025 Diabetes Care letter on splitting semaglutide pens for diabetes and 2026 pieces in Obesity whose titles describe "evidence gaps" (Komé 2025). The dose-ranging data that do exist point the other way: in SURMOUNT-1 the 5 mg arm lost 15.0% against 20.9% at 15 mg, and in SURPASS-2 semaglutide 1 mg produced several kilograms less loss than tirzepatide 10 or 15 mg (Jastreboff 2022) (Frías 2021). Lower doses do less; nobody has measured what a tenth of a dose does.

There is a legitimate version of the idea, and it lives inside the label: both labels let the clinician choose the lowest maintenance dose that works and is tolerated, which can be 1.7 mg of semaglutide or 5 mg of tirzepatide. What the labels do not support is treating a starting dose as a destination (Zepbound's label says 2.5 mg is not approved for maintenance), or splitting a brand pen into fractions it was not designed to deliver. And a "microdose program" built on a compounded copy does not escape the legal problem discussed below; a smaller amount of a copy is still a copy.

What happens when you stop

Both drugs were studied after withdrawal, and the answer is the same.

In the STEP 1 extension, 327 participants were followed for a year after semaglutide and the lifestyle program ended. The semaglutide group had lost 17.3% by week 68; by week 120 they had regained 11.6 percentage points, leaving a net loss of 5.6%, and their blood pressure, lipids and glucose had moved back toward baseline. The authors' summary: two-thirds of the weight loss returned within a year (Wilding 2022).

SURMOUNT-4 was designed around the question. After 36 weeks of open-label tirzepatide (mean loss 20.9%), 670 participants were randomized to continue or to switch to placebo for 52 weeks. Those who continued lost a further 5.5%; those on placebo regained 14.0%. Overall loss from the start was 25.3% with continued treatment versus 9.9% after stopping, and 89.5% of the continuing group kept at least 80% of their initial loss versus 16.6% of the placebo group (Aronne 2024).

The practical consequences: a price quote for three months is not the price of the treatment; stopping because the money ran out at month four returns most of the weight; and any plan should include either long-term continuation or a deliberate, clinician-managed taper with a maintenance strategy, knowing that the taper itself has not been studied.

Muscle loss and how it is managed

Losing 15 to 20% of body weight by any means, including surgery, removes lean tissue along with fat. In GLP-1 trials with body-composition substudies, the share of lost weight that was lean mass ranged widely, from about 15% or less in some studies to 40 to 60% in others; the authors of a 2024 review note that "lean mass" includes organs, bone and water, not just muscle, and that MRI studies suggest the muscle changes are largely proportionate to the weight loss and come with better muscle quality (less fat infiltration). The same review flags older adults and people with advanced disease as the group where sarcopenia is a real risk (Neeland 2024).

What clinicians do about it is standard weight-loss practice rather than drug-specific evidence: resistance training two or three times a week, enough protein (a common target is 1.2 to 1.6 g per kilogram of body weight a day, adjusted by a clinician for kidney disease), a slower titration when appetite suppression is making it hard to eat at all, and, in older adults, a baseline and follow-up measure of strength or body composition rather than weight alone. Drugs designed to preserve muscle during GLP-1 treatment are in development; none is approved. Clinics that sell growth hormone secretagogues alongside GLP-1s to "protect muscle" are selling a hypothesis; there is no trial of that combination.

Who should not take either drug

The contraindications and warnings are near-identical because the two drugs share a class (Wegovy label) (Zepbound label):

Medullary thyroid carcinoma or MEN 2. Both carry a boxed warning. Rodents given either drug develop thyroid C-cell tumors; whether humans do is unknown, and the drugs are contraindicated for anyone with a personal or family history of medullary thyroid carcinoma or multiple endocrine neoplasia type 2.
Prior serious hypersensitivity to the drug or its excipients.
Pregnancy. Both labels say to stop when a pregnancy is recognized. Because of semaglutide's week-long half-life, the Wegovy label says to stop at least two months before a planned pregnancy. Tirzepatide can reduce the effectiveness of oral contraceptives by slowing gastric emptying; the Zepbound label advises a non-oral method or a barrier method for four weeks after starting and after each dose increase.
Severe gastroparesis or other severe gastrointestinal disease: not recommended for either drug.
A history of pancreatitis. Neither label lists it as a contraindication, but both say to stop the drug if pancreatitis is suspected, and a history of it is a reason for a careful conversation rather than a routine prescription.
Diabetic retinopathy in people with type 2 diabetes: rapid improvement in glucose can temporarily worsen it; the labels call for monitoring.
Insulin or sulfonylureas: hypoglycemia risk rises; doses of those drugs usually need to be cut.
Kidney disease: acute kidney injury has occurred, mostly in people dehydrated by vomiting or diarrhea.
Planned surgery or sedation: both drugs slow the stomach, and aspiration under anesthesia has been reported; tell the anesthesiologist.
Type 1 diabetes is not an indication for either, and neither drug should be combined with another GLP-1 product.

Legal status of compounded versions after the shortages

The clinical sections above apply to both brand and compounded products. This section is where they part ways, and the legal tracker is the source of truth for the dates; the summary is:

The shortage window closed. FDA declared the tirzepatide shortage resolved on December 19, 2024, and the semaglutide shortage on February 21, 2025, with grace periods that ended in early 2025. Since then, a 503A pharmacy may compound either drug only for an individual patient when the prescriber documents a significant difference the approved product cannot provide, and never as a marketed copy; FDA has said that price or commercial availability alone is not such a need (FDA GLP-1 concerns page).
2026 enforcement. On March 3, 2026 FDA sent warning letters to 30 telehealth companies, and on June 16 to 25 more, 55 in total, over marketing that implied compounded GLP-1s were the same as, or approved like, the brand products.
The 503B proposal. On May 1, 2026 FDA published a Federal Register proposal not to include semaglutide, tirzepatide or liraglutide on the list of bulk substances that outsourcing facilities may use, which would end 503B production of GLP-1s if finalized (Federal Register, May 1, 2026).
Salt forms. FDA has also stated that some compounders used semaglutide sodium or semaglutide acetate, salt forms that are not the active ingredient of the approved products, and that it knows of no legal basis for compounding with them (FDA GLP-1 concerns page). Ask which form your pharmacy buys.
Research vials labeled "sema" or "tirz" and sold without a prescription are unapproved drugs; FDA's August 24, 2026 letters to five vendors said the research-use disclaimer does not survive dosing guides and bundled bacteriostatic water.

What this means in practice: a legal compounded GLP-1 prescription in late 2026 has a named state-licensed pharmacy, a prescriber who has written down why this patient cannot use Wegovy or Zepbound, and a label with a concentration. A subscription page that offers "compounded tirzepatide from $99" to anyone who fills in a form is the thing the warning letters were about.

The "with B12" and "with glycine" marketing

After the shortages ended, many compounders added an ingredient, most often cyanocobalamin (vitamin B12), sometimes niacinamide (B3), pyridoxine (B6) or glycine, so the product would no longer be an exact copy of the brand. The marketing attached benefits to the add-in: energy, less nausea, muscle preservation. None of those combinations has been tested in a weight-loss trial, and nothing in the STEP or SURMOUNT programs suggests a vitamin changes the result.

FDA's position has hardened. According to Frier Levitt's summary of the September 18, 2026 warning letter to Empower Pharmacy, FDA treated semaglutide-with-cyanocobalamin and tirzepatide-with-niacinamide as essentially copies of the approved drugs, said the production volume suggested the claimed differences were "pretextual", and objected to prescriptions whose clinical-need language was identical across many records or selected from a menu on a telehealth platform; an April 2026 FDA clarification had already used semaglutide plus B12 as an example of a product that can still be a copy when the route and strength match the brand (Frier Levitt 2026). For a patient the test is simple: if the B12 was added for you, after a conversation about why, that is medicine; if every customer gets B12, it is a workaround.

What each option costs in October 2026

Prices below are from our cost guide, collected on October 9, 2026, from manufacturer programs, the federal TrumpRx site and published price trackers.

Option	Typical monthly cash price	Notes
Wegovy injection (brand)	$349 through NovoCare; $199 for the first two fills for new patients in 2026; list about $1,350	Government-insured patients are excluded from the cash programs
Wegovy tablet	$149 at the starting dose to $299 at maintenance	Oral alternative, adults only
Zepbound vials or pens (brand)	$299 at 2.5 mg, $399 at 5 mg, $449 at 7.5 to 15 mg with on-time refills through LillyDirect; $499 to $699 otherwise; list about $1,086	TrumpRx average $346
Compounded semaglutide	$150 to $350 month to month; $100 to $200 on 3- to 12-month plans; lowest advertised $69 to $99	Legal only for documented individual need
Compounded tirzepatide	$180 to $300 typical; $99 to $399 full range; one 26-clinic tracker found a $332 month-to-month average	Maintenance doses cost more; cheapest plans need 6- to 12-month commitments
First-month extras	Consultation $0 to $200; labs $100 to $400; membership $0 to $100	Apply to brand and compounded programs alike

The brand prices fell by about two-thirds between early 2025 and 2026, which changed the arithmetic: at the lower doses, a compounded program saves a few hundred dollars a year against a labeled, FDA-reviewed pen, and at the higher tirzepatide doses the compounded price often climbs to meet the brand. Brand products may be covered by commercial insurance (widely for type 2 diabetes, with prior authorization for obesity); compounded products are cash, though a prescription usually qualifies for HSA or FSA funds.

Semaglutide or tirzepatide: who should choose which

Situation	Leans toward	Why
Maximum weight loss is the goal	Tirzepatide	20.2% versus 13.7% head to head; 57% of SURMOUNT-1 participants at 15 mg lost at least 20%
Established cardiovascular disease	Semaglutide	SELECT showed 20% fewer major cardiovascular events; the Wegovy label carries the indication, Zepbound's does not
Obstructive sleep apnea with obesity	Tirzepatide	On the Zepbound label
MASH with fibrosis	Semaglutide	On the Wegovy label
Type 2 diabetes with obesity	Either; tirzepatide for a larger HbA1c effect	SURPASS-2; Ozempic and Mounjaro are the diabetes-branded versions
Wants a pill	Semaglutide	Wegovy tablet, 25 mg daily at maintenance
Nausea or vomiting on one drug	Try the other, more slowly	Class effects are similar; individual tolerance differs; the labels allow slower escalation
Insurance covers only one	The covered one	Both are effective; coverage decides the price more than the molecule does
History of medullary thyroid carcinoma or MEN 2, or pregnant	Neither	Contraindicated or must be stopped
Planning pregnancy	Stop in advance	Two months before for semaglutide; tirzepatide stopped when pregnancy is recognized, with contraception caveats during treatment

Neither drug is the right answer for someone who wants a short course: both trials of withdrawal show the weight returning.

How to get it legitimately

See a clinician licensed in your state, in person or by telehealth, who takes a history that covers thyroid cancer, pancreatitis, gallbladder disease, diabetes medications, kidney function and pregnancy plans.
Start with the brand. With a prescription, the brand pens are available at retail pharmacies through insurance, or for cash through NovoCare and LillyDirect and the TrumpRx listings at the prices above. For most people in 2026 this is both the safest and, at low doses, nearly the cheapest route.
If a compounded product is proposed, ask why. A legitimate answer names a patient-specific reason the brand cannot meet, names the state-licensed 503A pharmacy, and produces a label with the drug, the concentration in mg/mL and the dose in mg and units.
Get the syringe explained and keep the units converter handy for the first few weeks.
Expect follow-up: dose adjustments every four weeks during escalation, someone to message about vomiting or abdominal pain, and a plan for maintenance before you reach it.

Red flags are the mirror image: "same as Wegovy" or "FDA-approved ingredients" in the marketing, no pharmacy named, a form instead of a consultation, B12 in every vial, "research grade" pricing, or a microdosing plan sold as maintenance.

Bottom line

Tirzepatide produces more weight loss than semaglutide, by about six to seven percentage points when each is pushed to its tolerated maximum, with a similar side-effect profile dominated by nausea and gastrointestinal upset during escalation. Semaglutide has the cardiovascular outcomes data, a liver indication and a pill. Both lose their effect when stopped, both take some lean mass with the fat, and both are contraindicated with a history of medullary thyroid cancer. Everything known about either drug was learned with the brand product; the compounded versions inherit the molecule's promise and add their own risks, from unit conversions to salt forms to a legal status that in 2026 depends on a prescriber's written reasons. If you can get the brand, get the brand. If you cannot, insist on the pharmacy's name, the concentration on the label, and a clinician who can explain why you are the exception.

Frequently asked questions

+Is the FDA banning compounded semaglutide?

Not with a ban, but with the ordinary rules. While Wegovy and Ozempic were in shortage, pharmacies could compound copies in volume. FDA declared that shortage resolved on February 21, 2025, and since the grace periods ended (April 22, 2025 for 503A pharmacies, May 22, 2025 for 503B facilities) a compounded semaglutide is legal only for an individual patient whose documented need the approved product cannot meet. In 2026 FDA sent 55 warning letters to telehealth companies over how compounded GLP-1s were marketed and proposed removing semaglutide from the list outsourcing facilities may use.

+Are compounded GLP-1s going away?

They are shrinking into the narrow lane the law always allowed. A clinician can still prescribe a compounded semaglutide or tirzepatide for a patient with a documented, patient-specific reason the brand product does not work (for example a true excipient allergy), filled by a state-licensed pharmacy. A website selling it to anyone at a discount, or adding vitamin B12 so it looks different, is the model FDA's 2026 letters targeted. The May 1, 2026 Federal Register proposal would also stop 503B outsourcing facilities from making either drug at all.

+What is the difference between semaglutide and tirzepatide?

Semaglutide (Ozempic, Wegovy) activates the GLP-1 receptor. Tirzepatide (Mounjaro, Zepbound) is a single peptide that activates both the GLP-1 and the GIP receptors. In the one head-to-head trial in adults with obesity but not diabetes (SURMOUNT-5, 751 participants, 72 weeks), tirzepatide at its maximum tolerated dose produced 20.2% weight loss versus 13.7% with semaglutide. Semaglutide has something tirzepatide does not yet have on its obesity label: a proven reduction in heart attacks, strokes and cardiovascular death in people with existing heart disease.

+Is compounded tirzepatide safe?

The molecule has the safety data of the brand trials; the compounded vial does not. Compounded products are not reviewed by FDA for potency, purity or sterility, are dispensed as multi-dose vials drawn up in insulin-syringe units, and FDA has received reports of patients injecting 5 to 20 times the intended dose after unit-to-milligram confusion. A compounded tirzepatide from a state-licensed pharmacy, prescribed by a clinician who wrote the dose in milligrams and units and explained the syringe, carries the known class risks (nausea, vomiting, gallbladder disease, rare pancreatitis). A vial sold as research-grade tirzepatide carries all of those plus an unknown content.

+What is the starting dose of compounded tirzepatide?

There is no separate dose for compounded tirzepatide; the only dosing with evidence is the Zepbound label: 2.5 mg once weekly for four weeks, then 5 mg, then increases of 2.5 mg no sooner than every four weeks to a maintenance dose of 5, 10 or 15 mg. The label says the 2.5 mg dose is for starting only and is not approved as a maintenance dose. In a vial at 10 mg/mL, 2.5 mg is 0.25 mL, or 25 units on a U-100 insulin syringe; at 20 mg/mL it is 12.5 units. Your pharmacy label overrides any chart.

+How many mg is 40 units of semaglutide?

It depends entirely on the concentration of the vial. 40 units is 0.4 mL on a U-100 insulin syringe. At 2.5 mg/mL that is 1 mg of semaglutide; at 5 mg/mL it is 2 mg; at 1 mg/mL it is 0.4 mg. Units measure volume, not drug, which is why every compounded prescription should state the dose in milligrams, the concentration in mg/mL and the units.

+Does tirzepatide cause hair loss?

Hair loss was reported by 5% of Zepbound patients at 5 and 15 mg (4% at 10 mg) versus 1% on placebo in the pooled trials, and by 3% of Wegovy patients versus 1% on placebo. The labels attribute it to rapid weight loss rather than to the drug itself, and it affected mostly women (7.1% of women versus 0.5% of men on Zepbound). It is usually temporary and did not lead any Zepbound patient to stop treatment in the trials.

+What happens if you stop taking semaglutide or tirzepatide?

Weight returns. In the STEP 1 extension, participants who had lost 17.3% on semaglutide regained 11.6 percentage points within a year of stopping, about two-thirds of the loss, and their blood pressure, lipids and glucose moved back toward baseline. In SURMOUNT-4, people who had lost 20.9% on tirzepatide in 36 weeks regained 14% over the following year on placebo, while those who continued lost a further 5.5%. Both trials describe obesity as a chronic condition that needs continued treatment or a deliberate maintenance plan.

+Where can I buy tirzepatide?

Legally, in three places: a retail pharmacy with a prescription (insurance or cash), Lilly's own LillyDirect program and the federal TrumpRx site for brand Zepbound vials at $299 to $449 a month depending on dose, or, for a patient with a documented individual need, a state-licensed compounding pharmacy on a clinician's prescription. Vials marketed online as research-use tirzepatide are unapproved drugs; FDA's 2026 warning letters treated dosing guides and bundled bacteriostatic water as proof they were being sold for human use.

+How do you inject tirzepatide in the stomach?

Subcutaneously, into the fat at least two inches from the navel, once a week on the same day, rotating sites each week; the thigh and the back of the upper arm are the other label sites. Brand pens are single-dose; compounded vials are drawn up with a U-100 insulin syringe after checking the dose in units against the concentration on the label. Our injection guide covers the technique step by step.