The short version

Plain English first. Everything below this section is the same material with the sources, the numbers and the caveats attached.

We do not sell this

Semaglutide is in this library as a reference entry. It is not in our catalogue, it never has been, and this page is written on the assumption that it never will be. What follows is the most honest account of it we can write — which is a different job from selling it, and an easier one.

Chemistry and pharmacokinetics quoted from the FDA Ozempic label, sections 11 and 12.3.

One detail from the chemistry that matters later

The label notes a “minor modification” at position 34 whose only purpose is “to ensure the attachment of only one fatty di-acid.” That modification exists because the di-acid can otherwise attach in the wrong place. So the manufacturing risk here is not simply “did you make the peptide” — it is wrong-position acylation, double acylation, and spacer-without-di-acid, all of which are semaglutide-shaped species a single purity percentage will not separate.

What is actually approved

On importing it yourself: CBSA Memorandum D19-9-1 para. 45 states plainly that “Canadian residents may not import prescription drugs by mail or courier,” and para. 43 requires personal-use imports to carry “the hospital, pharmacy dispensing or retail packaging, or have the original label affixed.” A vial couriered to a Canadian address fails the first on its face and the second by definition.

The evidence is strong. Say so.

A page that pretended otherwise would be factually wrong, and being wrong in the sceptical direction is still being wrong.

SUSTAIN-6 and FLOW quoted from FDA's own Ozempic label, section 14 — the regulator's account of the registration trials rather than the sponsor's. SELECT figures via the American College of Cardiology's trial summary; the journal full text would not open for us.

And now be exact about what has not been shown

That the weight loss persists after stopping. It has been tested, and it largely does not. The STEP 1 extension followed 327 people for 52 weeks off treatment: the semaglutide arm regained 11.6 percentage points against placebo's 1.9, and the paper's own conclusion is that “participants regained two-thirds of their prior weight loss.”

Long-term safety at the timescale people actually use it. The longest completed outcome exposure is SELECT at roughly 40 months mean follow-up. Obesity is lifelong and the weight benefit reverses on withdrawal. That is a statement about what the data covers, not an insinuation of harm.

And the sentence that carries into the rest of this page: every number above was generated with a metered device, a fixed formulation and clinical supervision. No trial has ever tested a self-titrated, self-measured, non-pharmacy preparation. None of this evidence transfers to a vial and a syringe by default.

One more that belongs beside the efficacy figures rather than buried: 74.2% of the STEP 1 treatment arm had a gastrointestinal adverse event, against 47.9% on placebo. Three in four.

What the label says

Approved drugs come with a document that lists their problems. That document is the single biggest thing a research vial does not have.

The full list of section 5 warnings: acute pancreatitis; diabetic retinopathy complications; hypoglycaemia with insulin or secretagogues; acute kidney injury from volume depletion; severe gastrointestinal reactions; acute gallbladder disease; and pulmonary aspiration during general anaesthesia or deep sedation. Common adverse reactions at 1 mg: nausea 20.3%, vomiting 9.2%, diarrhoea 8.8%.

Two post-approval findings, in opposite directions

A new one was found. In June 2025 the European regulator's safety committee concluded that non-arteritic anterior ischaemic optic neuropathy is “a very rare side effect of semaglutide” — defined as up to 1 in 10,000 — on evidence including large epidemiological studies showing roughly a “two-fold increase in the risk” in type 2 diabetes.

An old one was dismissed. In April 2024 the same committee concluded, verbatim, that “the available evidence does not support a causal association between the Glucagon-Like Peptide-1 receptor agonists … and suicidal and self-injurious thoughts and actions” — after a review covering non-clinical work, trials, post-marketing surveillance and two large electronic-health-record studies.

The anaesthesia point, which is about disclosure rather than the drug

Anaesthesiology guidance recommends holding weekly GLP-1 agonists a week before a procedure, because delayed gastric emptying raises the risk of aspiration under sedation. The guidance is candid that its evidence is “sparse limited only to several case reports.”

The risk is identical either way. What differs is that a person on a prescription has it on their medication list and a pre-op nurse sees it. A person injecting a grey-market vial has nothing on any list — not because they are reckless, but because there is nowhere for it to be written down.

The gap between an approved product and a vial

This is the whole argument, and it has nothing to do with the molecule. A correctly made semaglutide is a correctly made semaglutide. The medicine is not the molecule — it is the molecule plus a validated concentration, a preserved and buffered formulation, a sterility assurance, a metering device and a titration schedule. A vial is one of those five.

Concentration, and the arithmetic the manufacturer did so the patient would not have to

Novo Nordisk sells Wegovy in five presentations from 0.5 to 3.2 mg/mL. That is an expensive decision with one purpose: every rung of the escalation ladder is roughly the same injected volume. The arithmetic was removed from the patient's hands deliberately.

Now the vial. House arithmetic; U-100 syringe, 1 unit = 0.01 mL:

What is in the approved formulation that is not in a reconstituted vial

Per millilitre of Ozempic: disodium phosphate dihydrate 1.42 mg, propylene glycol 14 mg, phenol 5.5 mg, water for injection, pH approximately 7.4. Three of those do work that bacteriostatic water does not:

• Buffer. The approved product is phosphate-buffered to physiological pH. Bacteriostatic water is not buffered at all, so the pH a reconstituted powder lands at depends on the residual counterion and any bulking agent in that particular vial — neither of which the label declares.
• Preservative. Approved multi-dose products use phenol. Bacteriostatic water uses 0.9% benzyl alcohol — a different antimicrobial with a different spectrum. We found no published compatibility or stability study of semaglutide with benzyl alcohol.
• Bulking agent. A lyophilised vial almost certainly contains one. The labels we looked at declare none, and we verified nothing, so we are not going to name a candidate.

Sterility and endotoxin — and a correction that runs against our own argument

The relevant standards are USP <71> Sterility and USP <85> Bacterial Endotoxins. The endotoxin limit is K/M, with K = 5 EU/kg for non-intrathecal parenteral routes.

House arithmetic, 70 kg adult, maximum approved single dose 2.4 mg: M = 2.4 ÷ 70 = 0.0343 mg/kg, so the limit works out at roughly 146 EU/mg, and the total allowance for that dose is 350 EU.

What detectable endotoxin does mean is that it is a marker of bioburden during manufacture, and that the compendial ceiling is a specification for a validated, sterile-filtered product that must also pass a sterility test. Endotoxin is the measurable half of the problem. Sterility is the other half, and a purity certificate says nothing about either. We could not find a research vial of any peptide that ships with a USP <71> sterility result.

The salt question, which the label is silent on

FDA's cleanest line on this: “some semaglutide products sold by compounders may be the salt forms. These salt forms, including semaglutide sodium and semaglutide acetate, are different active ingredients than are used in the approved drugs.”

It bites harder for a research vial than for a compounding pharmacy, because a pharmacy at least has to answer for what it bought. A research label typically says “semaglutide” with no salt designation at all — silent on the exact question the regulator says is dispositive. A salt holds less peptide per milligram of powder than the free base. We could not source a peptide-content percentage for any specific semaglutide salt, so we are not printing a correction factor.

Why one purity number cannot carry this

A purity percentage from an HPLC integration tells you what fraction of the detected peptide is the target. It does not tell you what fraction of the vial contents is peptide at all, and for a site-specifically acylated peptide, wrong-position regioisomers may co-elute with the thing you wanted. A 99% number on a certificate is compatible with a great deal having gone wrong.

The approved ladder, and why a vial is not a course

The escalation schedule is the part of this medicine that cannot be shipped in a vial, and it is not a formality.

The label's own tolerance rule: “If patients do not tolerate a dose during dose escalation, consider delaying dose escalation for 4 weeks.” And note that the two ladders are not the same shape — Wegovy's is time-driven and fixed; Ozempic's is response-driven and conditional, increasing only “if additional glycemic control is needed.” A page that collapses them into one “semaglutide dosing schedule” is wrong.

The oral label makes the point even more plainly: the first month at 3 mg is described in the label itself as “not effective for glycemic control.” A full month of an approved medicine whose only stated purpose is letting the gut adapt.

A 5 mg or 10 mg vial is not a course of anything

House arithmetic from the table above. The escalation phase alone — sixteen weeks — consumes 13.8 mg. That is more than one 10 mg vial and nearly three 5 mg vials, before reaching the maintenance dose. A full year at the Wegovy ladder is 100.2 mg; a year of Ozempic to its 2 mg maximum is 87.0 mg.

On storage: the approved pen is good for 56 days in use, which is longer than our house 28-day convention. Both halves matter. Our 28 days is a handling convention and not a degradation cliff — we have no stability data for a benzyl-alcohol-preserved home reconstitution, and the one peer-reviewed paper on solution-state semaglutide degradation would not open for us. And the manufacturer's 56 days is not transferable: it was earned by a specific formulation in a specific container closure with a specific preservative, tested.

What actually goes wrong

Not theory. The regulator published the cases.

Read that against the arithmetic in the previous section. Every one of those is a unit-scale error, and the two ten-fold errors are precisely the failure mode a five-unit starting dose invites. A healthcare professional made one of them. This is not a careless-layperson problem. It is a decimal problem created by removing the metering device, and it lands on trained people too.

Poison centre data, with its caveat attached

A 2026 analysis of the US National Poison Data System covering 2012–2023 found 10,033 GLP-1 receptor agonist exposures, with reporting volume “more than doubled” after the mid-2021 weight-loss approval and semaglutide accounting for over 60% of cases thereafter. Severity shifted too — healthcare facility referrals rose from 23.0% to 33.5%.

The finding that matters most: “Most cases stemmed from unintentional dosing or therapeutic errors rather than deliberate misuse.” The two commonest mistakes were daily injections instead of weekly, and starting at a full dose rather than titrating.

FDA's own tally of adverse event reports for compounded semaglutide stood at more than 392 as of 30 November 2024. Reports do not establish causation, and the totals are likely undercounts because many state-licensed pharmacies are not required to report at all — but they are also a low rate against very large exposure. We are not going to make that number carry more weight than it can.

What has been found in the vials

Two separate stories, and the first one is not about the grey market at all.

Counterfeits reached licensed pharmacies

Three times in two years, counterfeit Ozempic entered the regulated US retail supply chain — December 2023 (lot NAR0074), April 2025 (lot PAR0362), December 2025 (lot PAR1229). On the first, FDA's laboratory confirmed “the needles from the samples are counterfeit” and warned that “the sterility of the needles cannot be confirmed, which presents an increased risk of infection.”

The published analysis of online-purchased semaglutide

A 2024 study in a major medical journal identified 317 online pharmacies, assessed 42% as illegal operations, and attempted purchases from six vendors. Three of six delivered; the other three never shipped and requested fraudulent extra payments. All three delivered products did contain semaglutide — and contained 29% to 39% more of it than the label claimed.

One more thing not to repeat: the widely-circulated claim that seized fake Ozempic contained insulin is not in the WHO alert that people cite for it. We read that alert — it names the falsified batches and states the risk in general terms, and it does not say what the falsified product contained. We could not source that claim anywhere, so we are not making it.

And in fairness the other way: Health Canada has issued recalls on approved semaglutide too, including one for an out-of-specification impurity. The difference is not that the regulated chain never fails. It is that when it fails, the failure produces a public, dated, classified record and a manufacturer obliged to act. A grey-market vial has no mechanism that generates such a record.

Regulatory status

This is the sharpest section, and the reason is counterintuitive: semaglutide's approval is what makes the “research chemical” framing collapse.

The FDA warning letters, one of which names our exact library entry

Three letters, read directly. In December 2024, two research-peptide sellers were warned over semaglutide on the same day. In February 2025, a third letter listed the products by name, in full: “Semaglutide (GLP-1 Analogue) 5mg” and “Semaglutide (GLP-1 Analogue) 10mg” — alongside “Bacteriostatic Water 20ml Vial” and “10 PACK OF INSULIN SYRINGES.”

The trap, and it is specific to approved drugs

A vendor cannot describe semaglutide accurately without describing an approved prescription drug for a disease. The accurate description is the drug claim. And FDA's misbranding argument closes the other exit, in its own words:

There is no wording that saves a semaglutide vial sold to the public. The disclaimer cannot be cured by writing better instructions, because no adequate instructions can exist. That is a stronger statement than we can make about most compounds in this library — and it is stronger because the drug is approved.

Canada

Health Canada's position on GLP-1 compounding, as relayed by a provincial college of pharmacists: most of it constitutes manufacturing rather than compounding, because it involves “unauthorized active pharmaceutical ingredients and duplication of currently available authorized manufactured products without unmet therapeutic need” — the concern being “particularly, but not limited to, semaglutide.”

And it has acted. A Type I recall, the most serious class, was issued on 21 January 2025 for a compounded semaglutide product from a pharmacy in Calgary, Alberta, on the grounds that it “was produced with an unauthorized active pharmaceutical ingredient.” In January 2026 Health Canada warned that retailers were selling unauthorised GLP-1 products in stores and online, with some sites “misusing official Health Canada logos and displaying fake endorsements.”

A precise negative, because it is the kind of thing a competitor page would blur: semaglutide does not appear on the 1 August 2025 Canada Peptide seizure advisory, which names sixty products. Tirzepatide and retatrutide do; “GLP-1 (7-37)” does, and that is the native peptide rather than semaglutide. That means one seizure did not include it. It does not mean Health Canada is relaxed about it — everything above says the opposite.

The United States, and a category error to expect

FDA declared the semaglutide shortage resolved on 21 February 2025, ending the enforcement discretion that had allowed widespread compounding. In May 2026 it published a notice proposing not to add semaglutide, tirzepatide and liraglutide to the 503B bulks list, its reasoning being that patient preference for an alternative formulation is not clinical need.

That was a notice, with comments closing 30 June 2026, and we could not find a final determination. So the accurate statement today is that FDA has proposed the exclusion, not finalised it. Anyone writing “FDA has banned it” is ahead of the document.

At the border, and in sport

FDA's Import Alert 66-80 allows detention without physical examination of GLP-1 active ingredient shipments except from firms on a green list. The figure worth carrying from it: FDA found 21% of 48 evaluated GLP-1 API sites were non-compliant with good manufacturing practice — roughly one in five of the facilities it inspected.

Semaglutide is not prohibited in sport, but it is monitored. WADA's own research record states that “In 2024, the Glucagon-like-peptide-1 (GLP-1) analog Semaglutide has been included in the WADA monitoring program,” with detection methods under development for blood and dried blood spots. Monitored substances are assayed — and a contaminated grey-market vial is the classic route to an adverse finding for something an athlete never intended to take.

Sentient Biogenix does not sell semaglutide.

Where the other side is right

Four arguments made by people we disagree with, each of which is better than it is usually given credit for.

Questions we actually get

Do you sell semaglutide?

No, and we do not intend to. It is in this library as a reference entry because people ask about it and because we would rather the honest page about it were also a page with nothing to sell.

Does it work?

Yes, and unusually well. A 17,604-patient cardiovascular outcomes trial in people without diabetes cut major adverse cardiac events from 8.0% to 6.5%. A 68-week weight trial produced 14.9% weight loss against 2.4% on placebo. Nothing else in this library is supported like that, and we are not going to pretend otherwise.

Then what is the problem with a research vial?

Nothing about the molecule. Everything about the other four things a medicine is: a validated concentration, a buffered and preserved formulation, sterility you can rely on, and a metering device. Every trial result above was produced with all four in place.

Does the weight come back?

Mostly, yes. In the STEP 1 extension, 327 people followed for a year after stopping regained about two-thirds of what they had lost — the paper says so in those words.

Is the 5 mg vial a course of treatment?

No. The escalation phase alone — sixteen weeks before you reach the maintenance dose — takes 13.8 mg. That is nearly three 5 mg vials, and a full year is around 100 mg. Vial sizes invite you to think in units of “a vial.” The approved schedule is not denominated that way.

Why is the starting dose the risky one?

Because it is the smallest volume. A 10 mg vial in 2 mL puts 0.25 mg at five units on an insulin syringe, so a one-unit misread is a 20% error. At the maintenance dose the same misread is 2%. The approved starter pen is ten times more dilute and delivers the dose in half a millilitre, which is not an accident.

Is it banned in sport?

Not prohibited — but it is on the monitoring programme and is actively being assayed. That matters mainly because a contaminated vial is the classic route to testing positive for something you never meant to take.

Isn't it on FDA's do-not-compound list?

No, and the reason is worth understanding rather than celebrating. That list handles substances with no approved product. Semaglutide has approved products, so it falls under a stricter mechanism instead. Its absence is not permission.

Can I bring some into Canada myself?

Border rules say Canadian residents may not import prescription drugs by mail or courier at all, and personal-use imports must carry pharmacy dispensing or original retail labelling — which a research vial by definition does not. And since April 2026 there are approved Canadian generics, so the question has a lawful answer it did not have two years ago.

References

1. US Food and Drug Administration. OZEMPIC (semaglutide) injection, prescribing information, NDA 209637 — chemistry §11, pharmacokinetics §12.3, dosing §2, trials §14, warnings §5, adverse reactions §6, storage §16, and the boxed warning. Read directly.
2. Novo Nordisk Canada. WEGOVY product monograph, and Health Canada Drug Product Database records DIN 02471469 (Ozempic) and DIN 02522551 (Wegovy) — indications, excipients, escalation table, authorisation dates.
3. Wilding JPH, et al. Once-weekly semaglutide in adults with overweight or obesity. New England Journal of Medicine 2021;384:989–1002. DOI 10.1056/NEJMoa2032183 — STEP 1.
4. Wilding JPH, Batterham RL, Davies M, et al. Weight regain and cardiometabolic effects after withdrawal of semaglutide: the STEP 1 trial extension. Diabetes, Obesity and Metabolism 2022;24(8):1553–1564. DOI 10.1111/dom.14725 — the two-thirds regain figure.
5. Lincoff AM, et al. Semaglutide and cardiovascular outcomes in obesity without diabetes. New England Journal of Medicine 2023;389:2221–32 — SELECT. Figures via the American College of Cardiology trial summary; the journal full text returned 403.
6. Sanyal AJ, Newsome PN, Kliers I, et al. Phase 3 trial of semaglutide in metabolic dysfunction-associated steatohepatitis. New England Journal of Medicine 2025;392(21):2089–2099. DOI 10.1056/NEJMoa2413258 — ESSENCE.
7. European Medicines Agency, PRAC. Recommendation on NAION, 6 June 2025; and conclusion on GLP-1 agonists and suicidal ideation, 12 April 2024. Both read directly.
8. US Food and Drug Administration. FDA alerts health care providers, compounders and patients of dosing errors associated with compounded injectable semaglutide products, 26 July 2024. fda.gov — the most useful single document on this page.
9. US Food and Drug Administration. Warning letters: Prime Vitality Inc. dba Prime Peptides, ref. 695156, 10 December 2024; Summit Research Peptides, ref. 695607, 10 December 2024; USApeptide.com, ref. 696885, 26 February 2025. All three read in full — the third names the 5 mg and 10 mg presentations, the bacteriostatic water and the syringes.
10. US Food and Drug Administration. Import Alert 66-80, detention without physical examination of GLP-1 receptor agonist bulk drug substances — the 21%-of-48 CGMP figure and the green-list mechanism.
11. US Food and Drug Administration. FDA clarifies policies for compounders as national GLP-1 supply begins to stabilize (21 February 2025); and Federal Register notice, 1 May 2026, proposing not to include semaglutide, tirzepatide and liraglutide on the 503B bulks list. A notice, not a final rule — comments closed 30 June 2026.
12. Health Canada. Generic semaglutide approvals, 28 April, 1 May and 29 June 2026; Type I recall of a compounded semaglutide product, 21 January 2025; public advisory on unauthorised GLP-1 products, 21 January 2026; and the 1 August 2025 Canada Peptide seizure advisory, checked by string for “semaglutide” and found absent.
13. Canada Border Services Agency. Memorandum D19-9-1, paragraphs 42–45 — personal importation of prescription drugs.
14. World Health Organization. Medical Product Alert N°2/2024: falsified OZEMPIC (semaglutide), 19 June 2024 — read directly, and it does not state what the falsified product contained.
15. Miller J, et al. National poison center trends in GLP-1 receptor agonist exposures following FDA approval for weight loss. Journal of Medical Toxicology 2026;22:275–285. Via two secondary accounts; the paper did not open.
16. Ashraf A, et al. Safety and risk assessment of no-prescription online semaglutide purchases. JAMA Network Open 2024. Could not open — the publisher served a CAPTCHA. Everything on this page from it is via four independent secondary accounts that agree, and its purity figure is deliberately omitted pending a reading of the original.

What we could not check, listed rather than hidden. The most consequential gap is the online-purchase study, whose reported purity and content figures are in tension and which we reached only second-hand — no purity number appears above because of it. We could not open a second online-seller surveillance dataset to cross-check it against, a peer-reviewed impurity analysis, the one paper on solution-state semaglutide degradation, a case series of compounded-semaglutide dosing errors, the SELECT and SUSTAIN-6 full texts, FDA's peptide-impurity guidance, or two Health Canada recall records. The FDA Category 2 negative rests on the 503A landing page and the Code of Federal Regulations; we did not open every linked table. The proposed 503B exclusion is a notice and not a final rule. We found no sourced peptide-content percentage for any semaglutide salt, so no mass-correction factor appears here. And the syringe error figures are arithmetic on a misread — we did not source the accuracy tolerance of a U-100 syringe at low fill volumes.