Overview
Overview
Semaglutide is a glucagon-like peptide-1 (GLP-1) receptor agonist with a prolonged half-life of approximately 7 days[1], approved for chronic weight management and glycemic control. The extended half-life enables once-weekly subcutaneous dosing, which is the standard clinical approach[1]. This educational protocol presents a gradual weekly titration from 0.25 mg up to a maintenance dose of 2.4 mg over 16+ weeks, using a practical dilution for precise insulin-syringe measurements. Reconstitute:
- Category
- Weight Loss
- Routes
- subcutaneous
Mechanism
Semaglutide
Mechanism of action
Mechanism of action
Semaglutide turns on a single target called the GLP-1 receptor . That receptor sits on cells in several different organs, which is why semaglutide affects hunger, blood sugar, the stomach, and the heart all at once. Two small changes to the natural GLP-1 molecule give semaglutide its long shelf life in the body. First, a tweak in the peptide chain blocks the enzyme (DPP-4) that normally breaks down GLP-1 within minutes. Second, a fatty acid chain lets semaglutide bind to albumin , a protein in the blood. That binding slows clearance and stretches the half-life to about 7 days, which is why one weekly injection is enough. GLP-1 receptors in the hypothalamus and brainstem signal fullness. Semaglutide turning these on reduces hunger and lowers calories eaten. In STEP 1, participants on 2.4 mg lost an average of 14.9% of body weight over 68 weeks. In the pancreas, semaglutide triggers insulin release - but only when blood sugar is already high. This 'glucose-dependent' behavior makes dangerous low blood sugar much less likely than with some older diabetes drugs. In the SUSTAIN trials, semaglutide cut HbA1c by 1.5-1.9% at the 0.5-1.0 mg doses. Semaglutide slows how fast the stomach empties. That stretches fullness after meals and blunts blood sugar spikes. It also explains the nausea and vomiting that are most common during dose escalation and usually fade with time. Semaglutide protects the heart and blood vessels in ways that go beyond weight loss alone. The SELECT trial showed a 20% drop in major heart events (heart attack, stroke, cardiovascular death) in people with obesity and existing heart disease. The benefit appeared even in people who did not lose much weight.
Key research findings
- 01
Semaglutide is a long-acting GLP-1 receptor agonist (an analog of human GLP-1), studied in once-weekly injectable and daily oral formulations (mechanistic / human study).
- 02
In the Phase 3 STEP program in adults with overweight or obesity, semaglutide produced substantial mean body-weight reduction versus placebo (human study, Phase 3; STEP 1, Wilding et al., New England Journal of Medicine, 2021).
- 03
In the SELECT cardiovascular outcomes trial, semaglutide was studied in adults with overweight/obesity and established cardiovascular disease (human study, Phase 3; NEJM, 2023).
- 04
Research describes GLP-1 receptor activation affecting appetite/satiety signaling and glucose-dependent insulin secretion (mechanistic).
- 05
Gastrointestinal effects are the most commonly observed effects in research (human study observation).
Primary source: Semaglutide has been studied in more clinical trials than any other GLP-1 medication - over 45,000 participants across multiple programs. Each trial name (STEP, SELECT, FLOW, ESSENCE) is its own program. STEP tested weight loss. SUSTAIN and PIONEER tested diabetes control. SELECT tested heart protection. FLOW tested kidney protection. ESSENCE tested fatty liver disease (MASH). SOUL tested cardiovascular outcomes for oral semaglutide. Major published semaglutide trials Trial STEP 1 (Wilding et al., NEJM 2021) Design Phase 3 / 68 weeks Population 1,961 adults with obesity, no diabetes Key result -14.9% body weight (semaglutide 2.4 mg) vs -2.4% placebo. 86.4% reached 5%+ loss. Trial STEP 2 (Davies et al., Lancet 2021) Design Phase 3 / 68 weeks Population 1,210 adults with T2D and overweight or obesity Key result -9.6% body weight (2.4 mg) vs -3.4% placebo. Trial STEP 3 (Wadden et al., JAMA 2021) Design Phase 3 / 68 weeks Population 611 adults with obesity + intensive behavior therapy Key result -16.0% body weight (2.4 mg) vs -5.7% placebo. Trial STEP 5 (Garvey et al., Nature Med 2022) Design Phase 3 / 104 weeks Population 304 adults with obesity, no diabetes Key result -15.2% body weight sustained at 2 years. Trial SELECT (Lincoff et al., NEJM 2023) Design Phase 3 / 39.8 mo mean follow-up Population 17,604 adults with CVD + overweight or obesity, no diabetes Key result 20% reduction in major heart events (HR 0.80; 95% CI 0.72-0.90; P<0.001). -9.4% body weight. Trial SUSTAIN-6 (Marso et al., NEJM 2016) Design Phase 3 / 104 weeks Population 3,297 adults with T2D at high CV risk Key result 26% MACE reduction (HR 0.74; 95% CI 0.58-0.95). First CV signal for semaglutide. Trial FLOW (Perkovic et al., NEJM 2024) Design Phase 3 / event-driven Population 3,533 adults with T2D and CKD Key result 24% reduction in kidney disease progression and CV death (HR 0.76; 95% CI 0.66-0.88). Trial ESSENCE (Sanyal et al., NEJM 2025) Design Phase 3 / 72 weeks (Part 1) Population Adults with MASH, F2-F3 fibrosis Key result 33% achieved both steatohepatitis resolution and fibrosis improvement vs 16% placebo. Trial SOUL (McGuire et al., NEJM 2025) Design Phase 3 / event-driven Population Adults with T2D + ASCVD or CKD Key result Oral semaglutide significantly reduced MACE vs placebo in high-CV-risk T2D. Trial STEP TEENS (Weghuber et al., NEJM 2022) Design Phase 3 / 68 weeks Population 201 adolescents (12-17) with obesity Key result -16.1% BMI reduction vs +0.6% placebo. Trial OASIS 4 (oral Wegovy) Design Phase 3 / 64 weeks Population Adults with obesity, no diabetes Key result -16.6% body weight at 25 mg daily. Basis for Dec 2025 oral Wegovy approval. ESSENCE Part 2 (240 weeks, liver outcomes) is ongoing, with results expected in 2029. Semaglutide has the largest clinical evidence base of any GLP-1 receptor agonist. Its FDA label has grown from a single T2D indication in 2017 to six approved indications by early 2026: type 2 diabetes, chronic weight management (injectable and oral), cardiovascular risk reduction, chronic kidney disease protection, and MASH.
Pharmacokinetic profile
Single-dose plasma curve over 24h. Shaded band = commonly-cited therapeutic window. Illustrative only.
Protocol Reference
Protocol reference
Commonly cited research range: 0.25–2.4 mg, weekly.
Reference figures reported in the research literature — not a dosing recommendation. For interactive vial math and scheduling, see the Calculator and Schedule tabs.
Cited protocol & reconstitution guide
Source-backed reference fields by phase, including any volume fields authored in the cited guide.
Weeks 1–4 (Initiation)
0.25 mg
Weeks 5–8 (Early escalation)
0.5 mg
Weeks 9–12 (Mid escalation)
1.0 mg
Weeks 13–16 (High escalation)
1.7 mg
| Phase | Reference amount | Units / volume |
|---|---|---|
| Weeks 1–4 (Initiation) | 0.25 mg | 10 units (0.10 mL) |
| Weeks 5–8 (Early escalation) | 0.5 mg | 20 units (0.20 mL) |
| Weeks 9–12 (Mid escalation) | 1.0 mg | 40 units (0.40 mL) |
| Weeks 13–16 (High escalation) | 1.7 mg | 68 units (0.68 mL) |
Titration protocol
- Weeks 1–4Start0.25 mg
Once weekly, same day each week. Starting dose. Rotate subcutaneous sites (abdomen, thigh, upper arm) between administrations.
- Weeks 5–8Build0.5 mg
Once weekly. Any step may be held an additional 4 weeks before moving up.
- Weeks 9–12Build1.0 mg
Once weekly.
- Weeks 13–16Build1.7 mg
Once weekly.
- Week 17+Maintenance2.4 mg
Once weekly, ongoing. Any scheduled increase may be delayed an extra 4 weeks at the current step; 1.7 mg weekly may be held for 4 weeks before returning to 2.4 mg. Source also lists alternate maintenance steps of 0.5, 1.0, or 2.0 mg weekly. Missed dose: if more than 2 days remain before the next scheduled dose, administer as soon as possible; if fewer than 2 days remain, skip it and resume the regular schedule.
Storage & Handling
Storage requirements(typical for most peptides)
Can be stored for extended periods. Protect from moisture.
Store in refrigerator door. Never freeze after reconstitution.
Label vials with reconstitution date. Discard if cloudy.
Reconstitution steps
- 01🌡️Bring to room temperature: let the lyophilized vial and the bacteriostatic water sit at room temperature for a few minutes.
- 02🧴Clean both stoppers with alcohol swabs; let air-dry about 10 seconds.
- 03💉Draw 0.8 mL bacteriostatic water into a sterile syringe — this 2 mg vial yields 2.5 mg/mL.
- 04💧Inject down the inside wall: push the water slowly down the inside of the vial wall; do not spray it directly onto the powder.
- 05🔄Swirl, do not shake: gently swirl until fully dissolved; the solution should be clear and colorless with no visible particles.
- 06🏷️Refrigerate: store at 2–8 °C (35.6–46.4 °F), protected from light, and use within 28 days; do not freeze the reconstituted solution.
- 07❄️Important: This guide is for educational purposes only and is not medical advice. For research use only. Not for human consumption.
- 08💉This 2mg vial covers the first 4 steps of the schedule; later steps exceed one vial.
Additional storage notes
Store at −20 °C (−4 °F) in a cool, dry place protected from light. For short-term storage (under a few months), 2–8 °C (35.6–46.4 °F) refrigeration is acceptable [7] . Avoid humidity to prevent peptide degradation.
Refrigerate at 2–8 °C (35.6–46.4 °F) and do not freeze [8] . Use within 28 days for maximum potency and safety; the benzyl alcohol in bacteriostatic water inhibits bacterial growth but solutions should still be discarded after approximately 4 weeks [9] .
Allow vials to reach room temperature before opening to minimize condensation uptake.
Clinical Evidence
Clinical evidence
Clinical trials demonstrate 15-20% body weight reduction. FDA-approved for chronic weight management. Improves cardiovascular outcomes.
Semaglutide has been studied in more clinical trials than any other GLP-1 medication - over 45,000 participants across multiple programs. Each trial name (STEP, SELECT, FLOW, ESSENCE) is its own program. STEP tested weight loss. SUSTAIN and PIONEER tested diabetes control. SELECT tested heart protection. FLOW tested kidney protection. ESSENCE tested fatty liver disease (MASH). SOUL tested cardiovascular outcomes for oral semaglutide. Major published semaglutide trials Trial STEP 1 (Wilding et al., NEJM 2021) Design Phase 3 / 68 weeks Population 1,961 adults with obesity, no diabetes Key result -14.9% body weight (semaglutide 2.4 mg) vs -2.4% placebo. 86.4% reached 5%+ loss. Trial STEP 2 (Davies et al., Lancet 2021) Design Phase 3 / 68 weeks Population 1,210 adults with T2D and overweight or obesity Key result -9.6% body weight (2.4 mg) vs -3.4% placebo. Trial STEP 3 (Wadden et al., JAMA 2021) Design Phase 3 / 68 weeks Population 611 adults with obesity + intensive behavior therapy Key result -16.0% body weight (2.4 mg) vs -5.7% placebo. Trial STEP 5 (Garvey et al., Nature Med 2022) Design Phase 3 / 104 weeks Population 304 adults with obesity, no diabetes Key result -15.2% body weight sustained at 2 years. Trial SELECT (Lincoff et al., NEJM 2023) Design Phase 3 / 39.8 mo mean follow-up Population 17,604 adults with CVD + overweight or obesity, no diabetes Key result 20% reduction in major heart events (HR 0.80; 95% CI 0.72-0.90; P<0.001). -9.4% body weight. Trial SUSTAIN-6 (Marso et al., NEJM 2016) Design Phase 3 / 104 weeks Population 3,297 adults with T2D at high CV risk Key result 26% MACE reduction (HR 0.74; 95% CI 0.58-0.95). First CV signal for semaglutide. Trial FLOW (Perkovic et al., NEJM 2024) Design Phase 3 / event-driven Population 3,533 adults with T2D and CKD Key result 24% reduction in kidney disease progression and CV death (HR 0.76; 95% CI 0.66-0.88). Trial ESSENCE (Sanyal et al., NEJM 2025) Design Phase 3 / 72 weeks (Part 1) Population Adults with MASH, F2-F3 fibrosis Key result 33% achieved both steatohepatitis resolution and fibrosis improvement vs 16% placebo. Trial SOUL (McGuire et al., NEJM 2025) Design Phase 3 / event-driven Population Adults with T2D + ASCVD or CKD Key result Oral semaglutide significantly reduced MACE vs placebo in high-CV-risk T2D. Trial STEP TEENS (Weghuber et al., NEJM 2022) Design Phase 3 / 68 weeks Population 201 adolescents (12-17) with obesity Key result -16.1% BMI reduction vs +0.6% placebo. Trial OASIS 4 (oral Wegovy) Design Phase 3 / 64 weeks Population Adults with obesity, no diabetes Key result -16.6% body weight at 25 mg daily. Basis for Dec 2025 oral Wegovy approval. ESSENCE Part 2 (240 weeks, liver outcomes) is ongoing, with results expected in 2029. Semaglutide has the largest clinical evidence base of any GLP-1 receptor agonist. Its FDA label has grown from a single T2D indication in 2017 to six approved indications by early 2026: type 2 diabetes, chronic weight management (injectable and oral), cardiovascular risk reduction, chronic kidney disease protection, and MASH.
- 01Semaglutide is a long-acting GLP-1 receptor agonist (an analog of human GLP-1), studied in once-weekly injectable and daily oral formulations (mechanistic / human study).
- 02In the Phase 3 STEP program in adults with overweight or obesity, semaglutide produced substantial mean body-weight reduction versus placebo (human study, Phase 3; STEP 1, Wilding et al., New England Journal of Medicine, 2021).
- 03In the SELECT cardiovascular outcomes trial, semaglutide was studied in adults with overweight/obesity and established cardiovascular disease (human study, Phase 3; NEJM, 2023).
- 04Research describes GLP-1 receptor activation affecting appetite/satiety signaling and glucose-dependent insulin secretion (mechanistic).
- 05Gastrointestinal effects are the most commonly observed effects in research (human study observation).
Evidence maturity varies by compound; much peptide research is preclinical (in vitro or animal-model). Where human data are limited, findings should be read as research observations, not clinical conclusions.
References
Literature references
Published research articles and sources related to Semaglutide.
- 01PMC – Once-Weekly Semaglutide for Weight Management: A Clinical Review — Comprehensive review of Semaglutide’s mechanism, efficacy, and safety in weight management (clinical data, half-life, GLP-1 receptor activation, weekly dosing) View Source
- 02PubMed – Semaglutide for Weight Loss in Obesity — Clinical trial data on Semaglutide efficacy and safety for chronic weight management View Source
- 03NCBI Bookshelf – Semaglutide (StatPearls) — Comprehensive pharmacology, clinical uses, dosing strategies, adverse effects, and contraindications for Semaglutide View Source
- 04Mayo Clinic – Semaglutide (Subcutaneous Route) — Clinical guidance on Semaglutide administration, side effects, dosing, and patient information including weekly protocol View Source
- 05PMC – Semaglutide 2.4 mg for Weight Loss: Clinical Evidence — Evidence-based review of Semaglutide 2.4 mg weekly maintenance dosing and clinical outcomes in obesity treatment View Source
- 06PubMed – Cardiovascular Outcomes with Semaglutide — Long-term cardiovascular safety and benefits observed in Semaglutide clinical trials View Source
- 07Dripdok – The Ultimate Guide to Storing Peptides — Best practices for peptide storage: temperature requirements, lyophilized vs. reconstituted storage, avoiding degradation View Source
- 08Wittmer Rejuvenation Clinic – How to Mix Semaglutide with Bacteriostatic Water — Practical guide for reconstituting Semaglutide with bacteriostatic water, storage after reconstitution, and 28-day use guidelines View Source
- 09Prime Peptides – How Much Bacteriostatic Water to Add to Peptides — Guidelines for bacteriostatic water reconstitution volumes, concentration calculations, and 28-day shelf life after opening View Source
- 10CDC – Vaccine Administration: Subcutaneous Route — Clinical guidelines for subcutaneous injection technique, angle of insertion, site selection, and no-aspiration protocol View Source
- 11Johns Hopkins Arthritis Center – How to Give a Subcutaneous Injection — Step-by-step patient education on subcutaneous injection technique, site rotation, hygiene, and disposal View Source
- 12CDC – How to Administer Intramuscular and Subcutaneous Vaccine Injections — Comprehensive injection technique guidelines, safety protocols, sharps disposal, and site-specific recommendations View Source
- 13NCBI Bookshelf – Best Practices for Injection Administration — Clinical best practices for aseptic technique, injection preparation, administration, and post-injection care View Source
- 14PMC – Subcutaneous Drug Injection: Pharmacologic Considerations — Review of subcutaneous route pharmacology, absorption kinetics, and clinical considerations for drug delivery View Source
- 15Pure Lab Peptides — Semaglutide (5 mg) product page: quality documentation, batch COAs, and research-grade peptide sourcing View Source
Observed Effects
Observed effects in cited research
Common stomach effects
- In pooled STEP 1-3 data on the 2.4 mg dose, nausea occurred in 43.9% of participants (vs 16.1% on placebo), diarrhea in 29.7% (vs 15.9%), vomiting in 24.5% (vs 6.3%), and constipation in 24.2% (vs 11.1%). These events were most common during the first 16-20 weeks of escalation and largely passed with time. 99.5% of GI events were non-serious and 98.1% were mild-to-moderate.
Dose-dependent pattern
- Lower diabetes doses (0.5-1.0 mg) produced stomach observed effects in 32.7-36.4% of participants vs 15.3% on placebo. That is meaningfully lower than the 2.4 mg obesity dose. Higher doses give bigger effects but also more observed effects.
Heart rate
- Resting heart rate rose by about 1-4 beats per minute in clinical trials. Despite this small increase, SELECT showed a 20% drop in major adverse cardiovascular events in people with existing heart disease and obesity. No rise in heart failure hospitalizations was observed.
Gallbladder and pancreatitis
- Gallstones were more common with semaglutide (about 2.6% vs 1.2% with placebo) in STEP, in line with rapid weight loss across all weight-loss interventions. Pancreatitis was rare but reported. Stop and seek care for severe abdominal pain.
Diabetic retinopathy
- In SUSTAIN-6 (T2D), retinopathy complications were higher with semaglutide (3.0%) than placebo (1.8%). The most likely cause is fast blood sugar improvement in people who already had retinopathy.
Thyroid boxed warning
- Semaglutide carries a boxed warning based on dose-dependent thyroid C-cell tumors in rodent studies. Human relevance is unknown. Semaglutide is contraindicated in anyone with a personal or family history of medullary thyroid carcinoma (MTC) or MEN 2.
Study and material context
Discontinuation
- In STEP, 6.8% of people on semaglutide 2.4 mg stopped treatment because of observed effects, vs 3.2% on placebo. The most common reasons were nausea (1.8%), vomiting (1.2%), and diarrhea (0.7%).
Research Considerations
Research considerations
Prescription medication. May cause nausea, requires gradual dose escalation. Consult healthcare provider.
- Personal or family history of medullary thyroid carcinoma (MTC) . Semaglutide carries a boxed warning based on thyroid C-cell tumors in rodent studies.
- Multiple Endocrine Neoplasia syndrome type 2 (MEN 2) .
- Known hypersensitivity to semaglutide or any ingredient in the formulation.
- Pregnancy and breastfeeding. Semaglutide is not approved for pregnancy. The label recommends stopping at least 2 months before a planned pregnancy because of the long half-life.
- History of pancreatitis. Pancreatitis has been reported in clinical trials. People with prior episodes need clinician oversight.
- Pre-existing diabetic retinopathy. In SUSTAIN-6, retinopathy complications were higher (3.0% vs 1.8% with placebo), likely tied to fast blood-sugar improvement in people who already had retinopathy.
- Gallbladder disease. Gallstones were more common with semaglutide (about 2.6% vs 1.2% with placebo) in the STEP trials, consistent with rapid weight loss in general.
- Severe gastrointestinal disease such as gastroparesis. Semaglutide already slows gastric emptying.
Factors noted in the research literature; not patient-specific medical advice.
Regulatory Status
Regulatory status
RUO
Comparisons
Comparisons
| Compound | Mechanism | Route | Status |
|---|---|---|---|
| Semaglutidethis | Activates GLP-1 receptors to increase insulin secretion, slow gastric emptying, and reduce appetite through central mechanisms. | subcutaneous | Investigational / RUO |
| SLU-PP-332 | A synthetic pan-agonist of estrogen-related receptors (ERR alpha/beta/gamma) studied for activation of an aerobic-exercise-like gene program and increased oxidative metabolism. | — | Investigational / RUO |
| Survodutide | An investigational long-acting dual agonist of GLP-1 and glucagon receptors studied for appetite regulation and increased energy expenditure. | subcutaneous | Investigational / RUO |
| Tirzepatide | Activates both GIP and GLP-1 receptors, providing synergistic effects on insulin secretion, glucose control, and appetite regulation. | subcutaneous | Investigational / RUO |
| 5-Amino-1MQ | Inhibits nicotinamide N-methyltransferase (NNMT), increasing NAD+ availability and enhancing mitochondrial metabolism. | oral, subcutaneous | Investigational / RUO |
| Semax | Increases BDNF expression, enhances dopamine and serotonin metabolism. Provides neuroprotection and cognitive enhancement. | nasal, subcutaneous | Investigational / RUO |
| Sermorelin | Binds to GHRH receptors to stimulate pulsatile GH release, mimicking natural patterns. Preserves feedback mechanisms. | subcutaneous | Investigational / RUO |
Attributes shown for research comparison only; not a statement of efficacy or therapeutic equivalence.
FAQ
Frequently asked questions
The FDA-approved starting dose for weight management (Wegovy) is 0.25 mg once weekly by subcutaneous injection. This dose is for tolerability only and is not considered therapeutic. After 4 weeks at 0.25 mg, the dose increases to 0.5 mg weekly, then steps up every 4 weeks through 1.0 mg and 1.7 mg until reaching the 2.4 mg maintenance dose by about week 17. For type 2 diabetes (Ozempic), the same 0.25 mg starting dose applies, but the maximum dose is 2.0 mg weekly.
Semaglutide has a half-life of about 7 days (165-184 hours), among the longest for current GLP-1 receptor agonists. A fatty acid chain attached to the peptide binds to albumin in the blood, which slows clearance. The 7-day half-life supports once-weekly dosing and means it takes about 4-5 weeks at each dose level to reach steady state. After stopping, semaglutide remains in the body for roughly 5-7 weeks.
In the STEP 1 clinical trial (NEJM, 2021), participants on semaglutide 2.4 mg lost an average of 14.9% of body weight at 68 weeks (about 33.6 lbs from a 232 lb average baseline) vs 2.4% with placebo. 86.4% achieved at least 5% loss, and about one-third reached 20% or more. STEP 3 with intensive behavior therapy showed 16.0% loss. STEP 5 showed sustained 15.2% loss at 2 years. STEP 2 in type 2 diabetes showed 9.6% loss.
Reconstitution applies to lyophilized (freeze-dried) research-grade semaglutide. Brand Ozempic and Wegovy pens come pre-filled and skip this step. A common setup is a 5 mg vial with 2.0 mL bacteriostatic water, which yields a 2.5 mg/mL concentration where 0.25 mg equals 10 units on a U-100 syringe. Inject water slowly down the vial wall, swirl gently (do not shake), and refrigerate at 2-8C. Use within 28 days. For custom math, use the Pep Pal calculator .
Yes. As of June 2026, semaglutide has broad FDA approval across multiple indications and brand names. Ozempic is approved for type 2 diabetes glycemic control (2017), cardiovascular risk reduction in T2D (2020), and CKD progression in T2D (February 2026). Wegovy is approved for chronic weight management (2021), cardiovascular risk reduction in adults with obesity and CVD (2024), and non-cirrhotic MASH with F2-F3 fibrosis (August 2025). The oral Wegovy 25 mg pill was approved in December 2025. Rybelsus is the older oral T2D form.
Stomach observed effects are most common. In pooled STEP 1-3 data on the 2.4 mg dose, nausea occurred in 43.9% (vs 16.1% placebo), diarrhea in 29.7% (vs 15.9%), vomiting in 24.5% (vs 6.3%), and constipation in 24.2% (vs 11.1%). These were most frequent during dose escalation, peaked around weeks 8-20, and were usually mild-to-moderate and transient. Permanent discontinuation due to observed effects was 6.8%. Semaglutide carries a boxed warning for thyroid C-cell tumors in rodent studies and is contraindicated in people with MTC or MEN 2.
Semaglutide is a single GLP-1 receptor agonist. Tirzepatide is a dual GLP-1 + GIP agonist. Retatrutide is a triple GLP-1 + GIP + glucagon agonist. In SURMOUNT-5 head-to-head, tirzepatide 15 mg produced -20.2% weight loss vs -13.7% for semaglutide 2.4 mg at 72 weeks. Retatrutide Phase 3 reported up to -28.7% at 68 weeks. Semaglutide's strength is depth of outcomes evidence: SELECT cardiovascular data, FLOW kidney protection, MASH approval (ESSENCE), and oral formulations.
Lyophilized semaglutide is commonly offered by research suppliers in 2 mg, 3 mg, 5 mg, and 10 mg vials. The 5 mg vial is the most common pick because it supports multiple weeks at typical doses and pairs cleanly with 2.0 mL bacteriostatic water for a 2.5 mg/mL mix. The 10 mg vial can be more cost-effective for higher-dose or longer protocols. Vial size and water volume should be chosen together, because they drive the syringe-unit math.
BAC water volume depends on vial size and desired concentration. For a 5 mg vial, 2.0 mL gives 2.5 mg/mL, where 0.25 mg = 10 units and 2.4 mg = 96 units on a U-100 syringe. For a 10 mg vial, 3.0 mL gives about 3.33 mg/mL, where 0.25 mg = 7.5 units and 2.4 mg = 72 units. A more concentrated 5 mg/mL option (5 mg in 1.0 mL) gives smaller draws but needs more precise syringe handling. Use the Pep Pal calculator for any custom setup.
The maximum FDA-approved subcutaneous dose is 2.4 mg weekly (Wegovy) for weight management. For type 2 diabetes (Ozempic), the maximum approved dose is 2.0 mg weekly. The oral maximum is 25 mg daily (Wegovy 25 mg pill, approved December 2025) or 14 mg daily (Rybelsus). In SELECT, the 2.4 mg dose produced a 20% reduction in major cardiovascular events. Published Phase 3 programs have not established higher subcutaneous maintenance doses than 2.4 mg weekly.
Reconstituted semaglutide should be refrigerated at 2-8C (35.6-46.4F) and used within 28 days. Do not freeze reconstituted semaglutide - freezing can degrade the peptide. Protect from light and label vials with the reconstitution date and concentration. Brand-name pens follow their own label rules: unused pens stay refrigerated, and after first use, pens can be stored at room temperature (up to 86F/30C) or refrigerated for up to 56 days.
No. Both are oral semaglutide, but they are different products with different maximum doses and approved indications. Rybelsus tops out at 14 mg daily and is approved for type 2 diabetes. The Wegovy 25 mg pill was approved in December 2025 for chronic weight management and tops out at 25 mg daily. Both must be taken on an empty stomach with a small sip of water, with no food, drink, or other medication for 30 minutes after.
No. Semaglutide is not insulin. It is a GLP-1 receptor agonist - a drug that copies the natural gut hormone GLP-1. It does cause the pancreas to release insulin, but only when blood sugar is already high (glucose-dependent insulin secretion). That is why semaglutide is much less likely to cause dangerous low blood sugar than direct insulin. Insulin works by directly adding the hormone insulin to the body. Semaglutide works by signaling the body to release its own insulin when it is needed.
As of June 2026, no generic semaglutide is FDA-approved in the United States. Novo Nordisk still holds active patents. The FDA-recognized shortage of semaglutide ended in 2025, which narrowed the legal scope of 503A/503B compounded semaglutide. Some countries have different patent timelines, with generic semaglutide expected in Canada earlier than the US. Verify current status with FDA orange-book listings and country-specific regulators before relying on this answer.
Use the Pep Pal calculator for exact dose-to-unit conversions. Enter vial size, BAC water volume, and target dose to get the matching syringe draw.
Browse the PepPal supplier directory for current supplier listings, or read the PepPal supplier rankings for ranked comparisons with Finnrick testing context.
Research-use notice
Research Use Only. This educational content and calculation support is intended for private research documentation. It does not provide medical advice, human-use directions, or claims of safety or effectiveness.