Compounded Semaglutide vs Ozempic and Wegovy: What's Actually Different

Semaglutide is a GLP-1 receptor agonist. The version a patient receives, and who checked it before it was sold, is where the real differences sit.

What is actually different?

Ozempic injection (NDA 209637) was approved on 2017-12-05 [7]. Rybelsus (NDA 213051) was originally approved on 2019-09-20; Ozempic tablets now appear under that same application [6]. Wegovy injection (NDA 215256) was approved on 2021-06-04 [3], and Wegovy tablets (NDA 218316) on 2025-12-22 [8].

Each is approved at fixed strengths, for example Wegovy injection at 0.25, 0.5, 1, 1.7, 2.4 and 7.2 mg [3].

Compounded semaglutide is prepared by a pharmacy for an individual patient on a prescription [10]. FDA states plainly that compounded drugs are not FDA approved and are not reviewed for safety, effectiveness or quality before they are marketed [1]. Its strength comes from the prescription, not from an approved label.

That is the central difference. A compounded product is made to a prescription; an approved product has a labeled dose, labeled warnings and trial data behind it.

What does a compounded vial contain?

Not automatically the same thing as an approved product, and the details matter.

FDA says semaglutide sodium and semaglutide acetate salts are different active ingredients from the approved drug, and that it is not aware of a lawful basis for their use in compounding [1]. For a compounded product that lists semaglutide as its active ingredient, adding an extra ingredient does not necessarily make it a different product in FDA's view: FDA says a semaglutide plus vitamin B12 injection may still be essentially a copy of the approved product if it is given by the same route and each strength is within 10% of the commercial strengths [10].

So the question to ask about any compounded vial is which form of semaglutide it contains and at what strength, not simply whether the word semaglutide appears on the label.

HealthRX.com offers compounded semaglutide by prescription.

Can pharmacies still compound semaglutide?

FDA announced on 2025-02-21 that the semaglutide injection shortage was resolved [10]. After a court denied the compounders' injunction request on 2025-04-24, the period of enforcement discretion ended for state-licensed pharmacies and physicians; for outsourcing facilities FDA said it would not act on shortage-dependent violations until 2025-05-22 [10].

What remains is narrower. A pharmacy may compound for an individual patient on a prescription, and FDA says it does not intend to act against a compounder for filling four or fewer prescriptions of an essentially copied product in a calendar month; a prescriber's documented significant difference for an individual patient is a separate exception [10]. Outsourcing facilities generally cannot compound from bulk substances unless the substance is on the bulks list or the drug is on the shortage list, and FDA says semaglutide is on neither [10].

On 2026-04-30 FDA proposed to exclude semaglutide, tirzepatide and liraglutide from the bulks list, finding no clinical need; comments were due 2026-06-29 and FDA says no final decision has been made [11].

What doses are approved?

Ozempic starts at 0.25 mg once weekly for 4 weeks, a dose the label says is not a maintenance dose, then 0.5 mg. Maintenance is 0.5, 1 or 2 mg, with increases no sooner than 4 weeks on the current dose; a missed dose can be given within 5 days [2]. For the kidney indication the label moves to 1 mg after at least 4 weeks at 0.5 mg [2].

For weight management, 2.4 mg weekly was the dose tested in STEP 1 [4]. STEP UP tested 7.2 mg weekly in 1,407 adults with obesity: mean weight change was a reduction of 18.7% on 7.2 mg, 15.6% on 2.4 mg and 3.9% on placebo [5].

Tablets are a separate dose set. Rybelsus is 3, 7 and 14 mg and Ozempic tablets 1.5, 4 and 9 mg, and the two are not substitutable on a mg-to-mg basis [9]. Wegovy tablets use 1.5, 4, 9 and 25 mg [8].

A compounded product has no approved dose. FDA reports dosing errors with compounded injectable semaglutide, including patients measuring the wrong dose and clinicians miscalculating [1].

What did the weight-loss trials actually test?

In STEP 1, 1,961 adults with a BMI of 30 or higher, or 27 or higher with a weight-related condition, were randomized to semaglutide 2.4 mg weekly or placebo for 68 weeks. Mean weight change was a reduction of 14.9% vs 2.4%, a difference of 12.4 percentage points, and 86.4% vs 31.5% lost at least 5% of body weight [4].

In STEP 4, 803 adults who reached 2.4 mg weekly were then randomized to continue or switch to placebo. From week 20 to week 68, weight fell 7.9% with continued semaglutide and rose 6.9% after switching to placebo [12].

In SELECT, 17,604 adults with established cardiovascular disease and a BMI of 27 or higher but no diabetes were followed for a mean of 39.8 months. Cardiovascular death, non-fatal heart attack or non-fatal stroke occurred in 6.5% vs 8.0% (hazard ratio 0.80, 95% CI 0.72 to 0.90) [13].

What should you watch for?

The semaglutide labels carry a boxed warning: in rodents semaglutide caused thyroid C-cell tumors at clinically relevant exposures, whether it causes them in humans is unknown, and it is contraindicated with a personal or family history of medullary thyroid carcinoma or MEN 2 [2]. The most common adverse reactions, at 5% or more, are nausea, vomiting, diarrhea, abdominal pain and constipation [2]. In pooled Ozempic trials, any gastrointestinal reaction occurred in 15.3% on placebo vs 32.7% on 0.5 mg vs 36.4% on 1 mg, and 0.4%, 3.1% and 3.8% stopped treatment for GI reasons [2].

For compounded products, FDA had received 990 adverse event reports as of 2026-05-31 and says the figure likely undercounts [1]. FDA also recommends discarding a multiple-dose vial 28 days after first use even if medicine remains, using a new sterile needle and syringe for every dose, and not using an injectable GLP-1 that arrives warm or with insufficient refrigeration [1]. FDA also warns of counterfeit Ozempic [1].