Semaglutide
/sem-ah-GLOO-tide/aka Ozempic, Wegovy, Wegovy HD
Long-acting GLP-1 receptor agonist that lowers appetite and blood sugar. An FDA-approved prescription drug, not a research peptide.
Semaglutide: educational research discussion. Not medical advice. Not a protocol for you.Details
- Reported range
- 0.25–2.4 mg weekly (7.2 mg HD)
- Frequency
- Weekly injection or daily tablet
- Cycle length
- 16-week titration, then continuous
- Half-life
- ≈ 1 week
- Route
- SC or oral
Reported figures describe what is published or discussed. None of them is a dose for you.
Mechanism
What it is proposed to do
Semaglutide is a modified copy of the gut hormone GLP-1. A fatty-acid side chain lets it bind albumin in the blood, which stretches its half-life to about a week. It activates GLP-1 receptors in the brain, pancreas and gut. Appetite drops, the stomach empties more slowly, and insulin release rises only when glucose is high. Most of the weight loss comes from eating less.
- 01
Semaglutide
GLP-1 analog with a fatty-acid chain; ~1-week half-life
established - 02
GLP-1 receptors
Brain, pancreas and gut
established - 03
Appetite ↓ · gastric emptying ↓ · insulin ↑
Insulin release is glucose-dependent
established - 04
Weight loss · fewer CV events
Shown in STEP and SELECT RCTs
established
Half-life. About 1 week per the label, so the drug stays in circulation for roughly 5 to 7 weeks after the last injection.
Dosing & cycles
What is reported, and where it comes from
Numbers below are labeled FDA label, clinical trial range or commonly reported range. They describe the published and discussed landscape. They are not instructions and not a protocol for you.
Dosing studio
Every figure is labeled by where it comes from.
Scale view: Wegovy injection label (weight management)
Probe at 1.32 mg: inside the reported band (0.25–2.4 mg). Drag it to read the scale. It does not pick a number for you.
Typical cycle, as a calendar
Wegovy label titration
16 weeks of steps, then continuous
The FDA label schedule: one injection a week, stepping up every 4 weeks to the 2.4 mg maintenance dose. There is no built-in end, because weight returns after stopping.
Cycle patterns
Wegovy label titration
The FDA label schedule: one injection a week, stepping up every 4 weeks to the 2.4 mg maintenance dose. There is no built-in end, because weight returns after stopping.
Stacks
What it gets combined with
Why people pair things, and what nobody has tested.
GLP + anything
3 compounds- Why people combine these
- People add repair or GH-axis peptides hoping to ease GI side effects or protect lean mass.
- Caution
- Semaglutide is the only tested drug in the mix. No interaction data exist, and if something goes wrong there is no way to tell which compound caused it.
- What is unknown
- No published human data on this combination: dosing, interactions and long-term effects are all unstudied.
Fat-loss layering
3 compounds- Why people combine these
- Pitched as adding a "metabolic" compound to a GLP-1 drug to break a plateau.
- Caution
- The GLP-1 drug has the trials. The add-ons have mouse data or a failed human trial. Layering them adds unknowns, not evidence.
- What is unknown
- No published human data on this combination: dosing, interactions and long-term effects are all unstudied.
Evidence
How much of this is known
Evidence grade
A
Strong human evidence
Multiple adequate human RCTs and/or FDA approval for a defined indication.
How we gradeGraded A on the strength of multiple large RCTs and FDA approval for weight management, type 2 diabetes and cardiovascular risk reduction. The evidence belongs to the approved product, not to compounded or gray-market copies.
Human trial status
STEP 1 (1,961 adults, 68 weeks): 14.9% mean weight loss on 2.4 mg vs 2.4% on placebo. SELECT (17,604 adults with cardiovascular disease and no diabetes): 20% relative reduction in major adverse cardiovascular events. STEP UP (72 weeks): 18.7% on 7.2 mg vs 15.6% on 2.4 mg and 3.9% on placebo. OASIS 4 (64 weeks): 13.6% on oral 25 mg vs 2.2% on placebo.
Limitations
- Benefits last only while treatment continues. In the STEP 1 extension, weight and cardiometabolic gains largely reversed within a year of stopping.
- Trials used the branded product. Compounded and gray-market versions were not tested.
- Part of the weight lost is lean mass, as with any large weight loss.
- The 7.2 mg dose adds about 3 percentage points of weight loss over 2.4 mg, with more GI effects and far more dysesthesia.
Sources to read
- Wilding JPH et al. Once-weekly semaglutide in adults with overweight or obesity, STEP 1 (NEJM 2021)
- Lincoff AM et al. Semaglutide and cardiovascular outcomes in obesity without diabetes, SELECT (NEJM 2023)
- Wharton S et al. Once-weekly semaglutide 7.2 mg in adults with obesity, STEP UP (Lancet Diabetes Endocrinol 2025)
- Wharton S et al. Oral semaglutide at a dose of 25 mg in adults with overweight or obesity, OASIS 4 (NEJM 2025)
- Wilding JPH et al. Weight regain after withdrawal of semaglutide: the STEP 1 trial extension (Diabetes Obes Metab 2022)
- WEGOVY prescribing information (DailyMed)
Links open PubMed, DailyMed, FDA or trial-registry searches. We do not cite what we have not described accurately.
Safety
Side effects, cautions, status
Commonly reported effects
- GI effects dominate: nausea, diarrhea, vomiting and constipation, mostly during dose escalation.
- Boxed warning: thyroid C-cell tumors in rodents, human risk unknown. Contraindicated with a personal or family history of medullary thyroid carcinoma or MEN 2.
- Label warnings include pancreatitis, gallbladder disease, kidney injury from dehydration, hypoglycemia with insulin or sulfonylureas, diabetic retinopathy complications and heart-rate increase.
- At 7.2 mg, dysesthesia (tingling, burning or altered skin sensation) affected 22% of patients vs 6% at 2.4 mg in label data.
- Weight regain after stopping: one year after STEP 1 treatment ended, participants had regained about two-thirds of the weight they lost.
Who should be extra cautious
- Medullary thyroid cancer or MEN 2 history. Contraindicated (boxed warning).
- Pregnancy or planning one. The Wegovy label advises stopping at least 2 months before a planned pregnancy because of the long half-life.
- Insulin or sulfonylurea users. Hypoglycemia risk rises in combination. The label addresses this directly.
- Pancreatitis or gallbladder history. Both are label warnings.
- Compounded or gray-market "sema". Not the approved product, and not what STEP or SELECT tested.
Legal & regulatory status
FDA-approved prescription drug, not a research peptide. Ozempic (2017) treats type 2 diabetes. Wegovy injection (2021) is approved for weight management, cardiovascular risk reduction and, under accelerated approval, MASH with liver fibrosis. Oral Wegovy 25 mg was approved December 22, 2025, and Wegovy HD 7.2 mg on March 19, 2026.
2026 compounding context. FDA declared the semaglutide shortage resolved in February 2025. Mass compounding of copies is no longer permitted, and "personalized" compounded versions are legally contested. A compounded product is not the drug tested in STEP or SELECT.
WADA. Not on the WADA Prohibited List. WADA has tracked it in its Monitoring Program since 2024 (tracked, not banned). Confirm with your federation.
Storage & handling, high level
Storage rules differ by product. Ozempic pens, for example, are refrigerated before first use and allowed up to 56 days once in use. Follow the label for the specific product, not a forum.
Reconstitution and injection technique are clinical skills. The reconstitution calculator does arithmetic only.
FAQ
Questions people ask about Semaglutide
Is semaglutide a research peptide?
What happens after stopping?
Is 7.2 mg just more of the same?
Can pharmacies still compound it?
Is it banned in sport?
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